After the Boston Planning and Development Agency (BPDA) unveiled the “PLAN: Mattapan” draft to the Greater Mattapan Neighborhood Council (GMNC) on Monday night, officials listened as residents reacted. “Will the neighbors have a say on these new units or can the property owner just build?” asked resident Louise Gant. “I can foresee there being problems.” Jared Staley, a BPDA