Affordable Housing; Revises upwards length of time that certain rental units must remain affordable in order to qualify for specified zoning variance; requires certain incentives be used for construction of affordable housing; revises upwards length of time that certain rental units must remain affordable in order to qualify for specified zoning variance; revises downward maximum median income used to determine eligibility for certain tax incentives; specifies that certain taxes do not apply to first-time homebuyers.