Talk about rental goals: this grand Park Slope mansion, just outside of Prospect Park, is chock full of historic details and could be yours for $29,000 a month. Located at 21 Prospect Park West, it is a Renaissance Revival home designed by the Brooklyn architect Montrose Morris. It’s been restored to its single-family grandeur, with over 7,000 square feet (and eight bedrooms!) practically dripping with features like stained glass, carved woodwork and marble fireplaces. Oh yeah, and there’s a diner inside that looks straight out of Happy Days.