Creates a new federal tax credit to turn older, non‑residential buildings (like offices or stores) into affordable rental housing. The credit equals 20% of eligible conversion costs. It sets rules for which costs qualify, requires a limited, state‑style allocation process, and includes extra provisions for distressed areas and historic rural projects. Properties must stay affordable for the long term, with reporting to prove compliance. The Treasury Department will issue regulations, and the credit applies to buildings placed in service after enactment.