Real property tax; partial exemption for repurposing underutilized structures for residential use; local incentives. Permits localities to provide partial real estate taxation exemptions for converted real property where such conversion establishes a residential structure that has set aside at least 30 percent of the structure for households with a per capita income at or below 80 percent of the locality's median income or where the building owner is subject to an agreement with the Commonwealth or the locality regarding the provision of affordable housing. Localities have discretion to determine (i) whether a converted building qualifies for the partial exemption, (ii) any additional restrictions and conditions, (iii) whether the exemption is the amount equal to the increase in assessed value or a percentage of such increase resulting from the repurposing of the structure, and (iv) the length of time the exemption will run with the land, not to exceed 15 years. The local governing body or its designee shall provide written notification of the partial exemption to the property owner. The bill also permits localities to grant tax incentives or provide regulatory flexibility to qualifying converted real property.