A Winnetka apartment complex has sold for the highest per-unit price in the neighborhood’s history, according to Matthews Real Estate Investment Services in El Segundo. The brokerage firm said that Keswick Manor, a 52-unit complex at 20135 Keswick St., sold for $13.25 million, or nearly $255,000 per unit. The investor bought the property under a limited liability entity named 303 WR, and it was sold by 6910 Kest Lp. The property was built in 1986 and includes a pool, spa, gated parking, elevators, laundry facilities and a gym. According to CoStar Group Inc., the buyer was Sussex Capital Group in Woodland Hills, and it was sold by JLS Investments, also in Woodland Hills. Last month, a 27-unit complex sold in Winnetka for $176,000 a unit, or $4.75 million. Daniel Withers, senior vice president of multifamily at Matthews, negotiated the deal on behalf of both parties. “Our comprehensive marketing plan and limited amount of non-rent control opportunities in the San Fernando Valley helped in getting a higher level of investor interest for this opportunity,” Withers said in a statement.