BOSTON — Locally based developer Chestnut Hill Realty Corp. will build Puddingstone at Chestnut Hill, a 250-unit mixed-income residential community at 201 Sherman Road in Boston’s Brookline area. The unit mix will consist of 90 one-bedrooms, 135 two-bedrooms and 25 three-bedrooms, with 50 residences designated as affordable housing for renters earning up to 30 or 50 percent of the area median income. Chestnut Hill will also construct a total of 377 parking spaces through a two-story deck and surface lots. MassDevelopment provided $126 million in both taxable and tax-exempt bonds for the project. A tentative completion date was not disclosed.