Sleek and Sized for Seniors: While prefabs can be an excellent option for just about anyone, Connect:Homes believes they're particularly ideal for downsizing seniors. Low-cost, move-in-ready, attractive and sustainable, they can be delivered anywhere in the U.S. Connect:Homes run as small as 640 square feet for a one bedroom up to 2,500+ square feet with 4 bedrooms and 2.5 baths.

How They Do It: Factory production cuts waste by 75 percent. Seventy percent of the elements in a Connect: Home are considered "environmentally preferable." Things like recycled glass counter tops, a cool roof system that reflects up to 90 percent of heat, and an efficient water heater that translates to a 40 percent energy savings.

Cost: $128,000 for 1 bedroom, 1 bath

Timeline: Under 2 months