Yowbarb Note: I cannot vouch for these ads. Nor do I get any compensation for posting them.
I look for ideas, stuff to move into and post stuff sometimes as I go...

This one below is upgraded, still not as large as many people would need but sleeps five. There is room for more built in, bedrolls, etc. The bunks that are already set in are double and extra long, larger bed on other side of bunker. Seems like additional underground areas would need to be set in for supplies, and connected to this shelter. Would need more storage for food and water, looks like. Ad said they do some customization... Going to post list of features. More on the page:
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http://www.risingsbunkers.com/ We offer the best underground bunkers, storm shelters and safe-rooms on the market. 100% steel, fabricated by hand and customized to each client's unique specs; our bomb shelters are the BEST on the market. Contact us today and get your free quote.
SURVIVAL SHELTER 10′ X 40′ UPGRADED MODEL – $ 95,500
This survival shelter offers a more open floor plan than the 20′ and 30′ models which allows for even more customization, bulk storage and shelving. In addition to more floor space this unit comes with our Bullet Resistant Door, Dining Table With Bench (Can Double As A Bed), Jack Knife Sofa (Doubles As An Extra Bed), 2 – Extra Long Double Bunks, 2 – Closets, NBC Air Filtration With Blast Valves and Over-pressure protection, Double Counter With Sink, Composting Toilet, Shelving For Food Storage, Water Pressure Pump, Shower, Hot Water Heater, Grey-Water Evacuation Tank, Grey-Water Evacuation Pump, Bathroom Door, 12 Volt LED Lighting, Solar Generated Charging System With Battery Supply, 12 Volt TV/DVD Combo, Fresh Water Inlet, 120/240 Volt Inlet, Staircase Handrail, Painted Interior and 150 Year Coating on the Exterior.
The 10×40 upgraded survival shelter is one of our most popular models because it offers all the protection you need while being spacious and unconfined. This large survival shelter offers comfortable sleeping for four or more with the jack knife sofa/bed. Included in this model is a dining table and bench style seating. There is more then enough counter top space with extra room throughout the entire survival shelter. This upgraded large survival shelter has all the features to keep your family ‘off-grid’ while being large enough to keep everyone content and happy.
Bullet Resistant Door
Side Entrance Staircase w/ Handrail
NBC Air Filtration with Blast Valves and Over pressure Valve
Water Filtration
Fresh Water Inlet
Private Bathroom w/ Composting Toilet
Full Shower
Water Pressure Pump
Water Heater
Grey-Water Evacuation Tank
Grey-Water Evacuation Pump
Full Kitchen
Alcohol Burning Stove
Dining Table With Bench
Double Counter
Shelving For Food Storage
Jack Knife Sofa (Doubles as Extra Bed)
Solar Generating Charging System with Battery Supply
12 Volt LED Lighting
12 Volt TV/DVD Combo
120/240 Volt Inlet
Painted Interior and 150 Year Coating on the Exterior