This bill significantly extends and modifies the Qualified Opportunity Zone (QOZ) program, aiming to prolong investment incentives and introduce new affordable housing requirements. It extends the period for which an area is designated as a QOZ from 10 to 20 years, providing a longer timeframe for community development. The legislation also extends the deadline for investors to elect to defer capital gains by investing in a Qualified Opportunity Fund (QOF) from December 31, 2026, to December 31, 2036. Consequently, the date for including deferred gains in income is also pushed back to December 31, 2036, for new investments, offering a longer deferral period. Furthermore, the bill introduces specific rules for residential rental projects within QOFs to promote affordability. To qualify for certain basis increases, at least 50 percent of occupied units must be for individuals with incomes at or below 100 percent of the area median income. The bill also increases the potential basis step-up percentages for these qualifying affordable housing projects. To be considered qualified opportunity zone property, residential rental projects must meet additional criteria, including that at least 30 percent of occupied units serve individuals with incomes at or below 100 percent of the area median income. These projects must also adhere to a 3 percent annual cap on rent increases and provide 60-day advance notice for any rent adjustments, ensuring tenant protections.