{"@context":"https://schema.org","@type":"Product","name":"7 Grand Design Momentum M-Class RVs for sale near Seffner","offers":{"@type":"AggregateOffer","offerCount":7,"lowPrice":"129995.00","highPrice":"174995.00","priceCurrency":"USD","offers":[{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-399m/48123aac-2814-11f1-9d95-02ea7b77d8a7/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 399M","description":"2026 Grand Design Momentum 399M, The 2026 Grand Design Momentum 399M is a luxury fifth-wheel toy hauler designed around flexible garage living, residential comfort, and extended-season durability. It s built for RVers who want the ability to haul toys, create a second living space, or simply enjoy a large rear flex room while still having a high-end, apartment-style main coach. At approximately 44 10 in length with a dry weight around 19,170 lbs and a GVWR of 23,500 lbs, it sits near the top of the Momentum lineup for size, capability, and premium features.

Inside, the 399M is all about versatility. Instead of a traditional fixed garage, the rear area is designed as a multi-use flex space that can function as a garage, lounge, office, guest room, or entertainment zone depending on how you travel. One of its signature features is the rear Party Patio system, which converts into an outdoor entertainment deck with integrated appliances and a large exterior entertainment wall effectively giving you a second living room outside the RV.

The main living area feels like a modern residential loft. With triple slide-outs, the center space opens up dramatically to include theater seating, a sofa, and a large entertainment center with fireplace. The layout is designed so that everyone in the coach can gather comfortably without feeling crowded, even on longer stays.

The kitchen is positioned as the heart of the coach, featuring a residential-style refrigerator (up to ~20 cu. ft.), 3-burner cooktop, oven, microwave, pantry storage, and a full countertop workspace, often with bar seating or a dinette that doubles as a work area. This makes the 399M especially popular with long-term travelers who want full cooking capability on the road.

Up front, the private master suite includes a queen or optional king bed, wardrobe storage, and washer/dryer prep, giving it a true residential bedroom feel. The adjoining bathroom features a large walk-in shower, porcelain toilet, and vanity storage, designed for extended use rather than weekend camping.

From a construction standpoint, the 399M is built on Grand Design s heavy-duty Momentum platform, including 101 wide-body construction, laminated fiberglass walls, triple axles, and a fully enclosed and heated underbelly for extended-season camping. It also includes a 6-point hydraulic leveling system, multiple power awnings, and large pass-through storage, making setup and campsite living easier despite its size.

Reasons to Buy the 2026 Momentum 399M Unique garage-to-living flex space design Rear Party Patio outdoor entertainment system Bar/Dinette Swivel Table Spacious residential main living area with triple slides Full kitchen with residential refrigerator and pantry storage Private master bedroom with washer/dryer prep ","itemCondition":"Used","priceCurrency":"USD","price":"149994.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-399m/35979ebb-d4d9-11f0-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 399M","description":"2026 Grand Design Momentum 399M, The 2026 Grand Design Momentum 399M is a premium luxury toy hauler fifth wheel built for RVers who want a true combination of residential living space, large garage flexibility, and high-end extended-season construction. At approximately 44 10 45 in length with a dry weight around 18,000 lbs and a GVWR of 22,500 23,500 lbs, this model sits in the upper tier of the Momentum lineup and is designed for serious travelers who still want upscale comfort at camp.

Inside, the 399M stands out because it s not just a traditional toy hauler it s designed as a flex-living platform where the rear garage can function as a cargo space, office, lounge, or additional sleeping area depending on your needs. The garage includes a large ramp door that converts into a patio deck, extending your living space outdoors and creating a second entertainment zone beyond the main cabin.

The main living area feels more like a modern apartment than a garage-based RV, featuring opposing slide-outs, theater seating, a sofa, and a residential entertainment center with a fireplace. A central kitchen island anchors the space, giving you real countertop workspace, while large windows throughout the slide-outs bring in natural light and open up the interior when fully set up.

The kitchen is built for full-time travel use, offering a large residential refrigerator (up to ~20 cu. ft.), 3-burner cooktop, oven, microwave, and deep sink with solid-surface countertops, plus a full pantry for extended trips. This makes it easy to cook for families or groups without relying on campground amenities.

Up front, the private master bedroom includes a queen bed slide (king optional), wardrobe storage, and washer/dryer prep, giving owners a true residential retreat. The adjacent bathroom includes a large walk-in shower, porcelain toilet, and vanity storage, designed for comfortable daily use even during long-term stays.

One of the defining strengths of the Momentum 399M is its dual-living-zone design, separating the garage and main coach so multiple groups can coexist without feeling crowded. The garage itself can include a half bath, additional sleeping options, and entertainment setup, making it extremely versatile for families, toy haulers, or mobile lifestyle users.

Built on Grand Design s Momentum platform, the 399M features laminated fiberglass construction, a fully enclosed and heated underbelly, and heavy-duty triple-axle running gear, making it capable of extended-season camping and demanding road travel. Exterior highlights typically include multiple power awnings with LED lighting, a 6-point hydraulic leveling system, and large pass-through storage, ensuring easy setup and strong campsite stability.

Reasons to Buy the 2026 Momentum 399M Massive garage-to-patio conversion for indoor/outdoo","itemCondition":"Used","priceCurrency":"USD","price":"174995.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-394m/37a34f87-d4d9-11f0-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 394M","description":"2026 Grand Design Momentum 392M, The New 2026 Grand Design Momentum 392M is a luxury toy hauler fifth wheel built for buyers who want serious cargo capacity without giving up upscale residential comfort. At 45 feet 11 inches long with three slide-outs and sleeping for up to 9, the 392M delivers the kind of space, flexibility, and premium design that makes it ideal for both adventure-focused travel and extended stays. Grand Design lists this floorplan with a 3,650-pound hitch weight, 18,114-pound UVW, and 23,500-pound GVWR, underscoring its heavy-duty capability and premium toy hauler construction.

One of the biggest highlights of the 392M is its 17-foot garage, giving owners ample room for motorcycles, side-by-sides, golf carts, or other gear while still maintaining a highly livable interior. Dealer listings for the 2026 model also highlight sought-after features like an L-shaped sofa with recline, queen bed, overhead loft bed, bath and a half, and a ramp door patio, making this coach especially attractive for families, groups, or buyers who want toy hauler versatility with luxury fifth wheel comfort.

Beyond the garage, the Momentum 392M is designed to feel premium and travel-ready. Published specs for current 2026 units show 140 gallons of fresh water, 104 gallons of gray water capacity, 52 gallons of black water capacity, 45,000 BTU of A/C, a 35,000 BTU furnace, tankless water heater, and an NPS 6000 generator, all of which support longer trips and a more self-contained camping experience. The Momentum brochure also emphasizes the line s upscale positioning as a high-end toy hauler built for buyers who want to bring their gear while still enjoying luxury on the road.

For shoppers looking for a high-capacity toy hauler with luxury living space, strong sleeping capacity, and a garage built for real adventure, the New 2026 Grand Design Momentum 392M stands out as an impressive choice.

Why buy from Lazydays RV powered by Campers Inn?

Wide selection of new and pre-owned RVs in one convenient location Knowledgeable RV professionals to help match you with the right coach Financing options to help make ownership more accessible Trade-in assistance to simplify the buying process A trusted dealership experience backed by recognized names in the RV industry

","itemCondition":"Used","priceCurrency":"USD","price":"154995.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-414m/3f4c0649-d4da-11f0-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 414M","description":"2026 Grand Design Momentum 414M, The 2026 Grand Design Momentum 414M is a flagship luxury toy hauler fifth wheel built for maximum space, residential comfort, and serious hauling capability, making it one of the largest and most feature-packed models in the Momentum lineup. At approximately 46 4 in length with a dry weight around 18,500 lbs and a GVWR of 23,500 lbs, it s designed for full-time RVers, large families, or outdoor enthusiasts who want a true combination of garage utility and high-end living space.

Inside, the 414M is centered around a 14-foot separate garage, giving you dedicated space for ATVs, motorcycles, golf carts, or additional storage. This garage isn t just for hauling it converts into a secondary living area with drop-down beds, seating, loft space, and even a half bath, making it ideal for guests or multi-family travel.

The main living area offers a wide-open residential layout with triple slide-outs, creating a large central gathering space. Theater seating or reclining sofas face an entertainment center with a fireplace, while large windows bring in natural light and make the space feel even more expansive when set up at camp.

The kitchen is one of the standout features of the 414M, designed for full-time usability with a U-shaped or extended countertop layout, bar seating, pantry storage, and a 20 cu. ft. residential refrigerator. Combined with a 3-burner cooktop, oven, and microwave, it provides everything needed for long trips without sacrificing cooking space or storage.

Up front, the private master suite includes a queen bed slide (king optional), large wardrobe storage, and washer/dryer prep, giving it a true residential bedroom feel. The main bathroom features a large walk-in shower with seating, vanity, and porcelain toilet, while the garage half bath adds extra convenience especially for families or guests.

Built on Grand Design s premium Momentum platform, the 414M includes 101 wide-body construction, triple axles with independent suspension, a fully enclosed and heated underbelly, and high R-value insulation (R-45 floor, R-40 roof), making it suitable for extended-season and even cold-weather camping. Exterior features typically include three power awnings, a 6-point hydraulic leveling system, fuel station, and large pass-through storage, ensuring both comfort and capability on the road.

Reasons to Buy the 2026 Momentum 414M Massive 14 separate garage with convertible living space Bath-and-a-half layout for added convenience One of the largest Momentum models (~46 4 ) Spacious residential living area with triple slides High-end kitchen with 20 cu. ft. refrigerator and large prep space Sleeps up to 6 7 people comfortably Loft + garage sleeping adds flexibility Triple-a","itemCondition":"Used","priceCurrency":"USD","price":"129997.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-414m/42a681cf-d4da-11f0-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 414M","description":"2026 Grand Design Momentum 414M, The 2026 Grand Design Momentum 414M is a flagship luxury toy hauler fifth wheel built for maximum space, residential comfort, and serious hauling capability, making it one of the largest and most feature-packed models in the Momentum lineup. At approximately 46 4 in length with a dry weight around 18,500 lbs and a GVWR of 23,500 lbs, it s designed for full-time RVers, large families, or outdoor enthusiasts who want a true combination of garage utility and high-end living space.

Reasons to Buy the 2026 Momentum 414M Massive 14 separate garage with convertible living space Bath-and-a-half layout for added convenience One of the largest Momentum models (~46 4 ) Spacious residential living area with triple slides High-end kitchen with 20 cu. ft. refrigerator and large prep space Sleeps up to 6 7 people comfortably Loft + garage sleeping adds flexibility Triple-a","itemCondition":"Used","priceCurrency":"USD","price":"129997.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-399m/333bf889-d4da-11f0-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 399M","description":"2026 Grand Design Momentum 399M, The 2026 Grand Design Momentum 399M is a premium luxury toy hauler fifth wheel built for RVers who want a true combination of residential living space, large garage flexibility, and high-end extended-season construction. At approximately 44 10 45 in length with a dry weight around 18,000 lbs and a GVWR of 22,500 23,500 lbs, this model sits in the upper tier of the Momentum lineup and is designed for serious travelers who still want upscale comfort at camp.

Reasons to Buy the 2026 Momentum 399M Massive garage-to-patio conversion for indoor/outdoo","itemCondition":"Used","priceCurrency":"USD","price":"149995.00"}},{"@type":"Offer","url":"https://www.rvt.com/buy/details/2026-grand-design-momentum-m-class-344m/ffa600c9-0c9a-11f1-beaa-02c8259c7411/","itemOffered":{"@type":"Thing","name":"2026 GRAND DESIGN MOMENTUM M-CLASS 344M","description":"2026 Grand Design Momentum 344M, Get ready to elevate every adventure with the all-new 2026 Grand Design Momentum 344M a luxury fifth wheel toy hauler designed for those who refuse to compromise between rugged capability and residential comfort. Whether you're hauling your favorite toys or simply craving wide-open space and premium amenities, the Momentum 344M delivers a next-level RV experience that turns every trip into something unforgettable.

From the moment you arrive, the Momentum s bold exterior styling, high-gloss fiberglass finish, and rugged stance make a statement. Step inside and you ll immediately notice the expansive living area, thanks to opposing slide-outs that create a wide, open floorplan perfect for relaxing or entertaining. The garage area offers incredible versatility haul your motorcycles, ATVs, or golf cart with ease, then transform the space into a guest suite, lounge, or even a mobile office.

The interior is thoughtfully crafted with high-end finishes and residential touches throughout. Plush seating, solid surface countertops, hardwood cabinetry, and premium lighting create a warm, inviting atmosphere. The kitchen is a chef s dream, featuring stainless steel appliances, a large refrigerator, a spacious pantry, and plenty of prep space perfect for everything from quick meals to full family dinners.

When it s time to unwind, the master suite provides a private retreat with a comfortable king bed, generous wardrobe storage, and washer/dryer prep for extended stays. The spa-inspired bathroom includes a large shower with glass doors, modern fixtures, and plenty of room to get ready for the day ahead.

The Momentum 344M is also built for true four-season travel. With Grand Design s superior insulation package, heated underbelly, and high-performance HVAC system, you can confidently explore in any climate. Add in the industry-leading garage tie-down system, fuel station, and ramp door patio, and you ve got a toy hauler that s as functional as it is fun.

Tech-savvy travelers will appreciate the integrated control systems, allowing you to manage lighting, slides, temperature, and more right from your smartphone. Multiple entertainment options, including large LED TVs and premium sound systems, ensure you re always ready for movie night or game day, wherever you roam.

Why buy the 2026 Grand Design Momentum 344M? Because it offers the perfect balance of adventure and luxury. It s spacious, versatile, and built with the quality and attention to detail Grand Design is known for. Whether you re heading to the mountains, the beach, or your favorite off-grid destination, this toy hauler gives you the freedom to bring everything and everyone along for the ride.

And when it comes to where you buy, Lazydays Powered by Campers Inn RV stands above the rest. With decades of experience and a reputation for exceptional customer service, they make your RV buying journey smooth, transparen","itemCondition":"Used","priceCurrency":"USD","price":"129995.00"}}]}}