4. Backup power generator: Homeowners who obtain a backup power generator recoup on average only about 59 percent of the project's cost when they sell the home, according to the report. Although most homeowners don't consider a backup power generator essential, its popularity varies a great deal from one region to another. Those living in communities where tornados, hurricanes, or blizzards could knock out power for days are more likely to be drawn to homes with this feature, Alfano says. "Being out of power in Florida might not be that big of a deal in February, whereas in Vermont [a backup power generator] makes a huge difference," Alfano says.
5. Garage addition: Homeowners who build a garage addition recoup on average about 62 percent of the project's cost when they sell the home, according to the report. Lipford argues that the limited versatility of a garage doesn't necessarily justify its high cost, which can average more than $58,000. A garage addition project is a labor intensive effort, often requiring builders to pour a slab, construct walls, and build a roof, among other things. "The only thing that is keeping it from being legitimate living space is insulated walls for air conditioning and heating—so it does represent a high cost to do that for strictly sheltering cars [or storing belongings]," Lipford said. "So when you start going down the check list of things you have to do, [the garage addition] starts moving down the list."