The Assisted Housing Stability and Energy and Green Retrofit Program awards about $2 billion for project-based rental assistance and $250 million for energy retrofit and green investments in assisted housing. The funds are provided by the HUD. As a real estate investor applying for grant assistance to be used on energy retrofits for your property, be prepared to show how your housing assists low income families. The HUD determines the amount one qualifies for and the grant money must be spent over a two-year period. You must commit to maintaining rents within affordable margins.