What incentives could provide relief for developers if they add affordable housing to their buildings?

According to studies of Harvard Street, the best economic use of the ground floor will be commercial, because owners can get higher rents from commercial leases than residential leases. According to the Harvard Street zoning proposal, new buildings could be four stories high, and, according to Brookline’s inclusionary zoning by-law, 15% of the units must be deemed affordable to lower income people.

In addition, the MBTA-CA Consensus Warrant Article includes a ground floor commercial incentive that provides a tradeoff to developers: by investing in the build-out of their ground floor commercial space, developers can earn more income from their affordable units

Will MBTA-CA compliance create affordable housing in Brookline?

How do MBTA-CA Guidelines constrain Brookline’s ability to create affordable housing?