New York City — KFIR Capital, a New York-based firm, has arranged the $20.5 million sale of a multifamily property in Brooklyn. The 43,000-square-foot building at 210 Clarkson Ave. was vacant at the time of sale, formerly housed a Dollar Tree store and a private school. The buyer plans to develop part of the building into a residential property. Jake Blatter of KFIR represented the seller, New York-based 210 Clarkson Corp., in the transaction. Blatter also represented the buyer, a local investor.