Chestnut Hill Realty has acquired 1443 Beacon St., a 115-unit luxury apartment complex near Brookline’s Coolidge Corner.

The original developer and longtime owner, Sydney Assoc. of Brookline, sold the asset for $73.5 million.

The property was 100 percent leased at the time of the sale, said Stephen Gladstone, senior acquisitions manager for Chestnut Hill Realty.

“It’s a great building – if not the premier rental property – in Brookline, then it’s right up there,” Gladstone said.

The purchase price works out to over $639,000 per unit.

Built in 1980, the complex contains 75 one-bedroom units renting for an average of $2,900, 34 two-bedroom units with an average rent of $3,950 and six three- and four-bedroom units renting for an average of $5,000. The property also contains two commercial spaces used by medical tenants.

Chestnut Hill Realty will keep the property as a rental complex, Gladstone said. It plans landscaping upgrades and a rolling renovation of the apartments, corridors and amenity package.

People’s United Bank provided a $45 million mortgage for the acquisition.