Cayre-Synergy 73rd, LLC, a joint venture of Midtown Equities and Synergy, has opened a sales office for Blanca, a new 10-unit residential condominium building it is developing at 206 East 73rd Street.

The six-story building between Third and Second Avenues has a triplex penthouse, two four-bedroom, triplex maisonette apartments and 7 two-bedroom loft units.

Michael Gadaleta of MG New York is the architect.

Prices for the apartments, which will be available for occupancy in September, range from $2.2 to $5 million, according to Shaun Osher, president of CORE Group Marketing.

Two tri-level maisonettes offer four bedrooms, three baths, two powder rooms and a cellar with a wide open area complete with wet bar. The units have about 3,300 square feet of space, fireplaces and French doors leading to an outdoor patio and garden.

Two-bedroom lofts with 1,633 square feet of indoor space and balconies and terraces.

The three-level, three-bedroom penthouse has over 4,000 square feet of interior and exterior space. It features a two-story living room with a dramatic 20-foot ceiling and a fireplace, as well as a glass wall with sliding glass doors that open to a 400-square-foot terrace. The third level has a 1,000-square-foot private roof deck.

The building has a cast stone facade with glass balconies and a private-key elevator.

Each apartment includes a SieMatic kitchen with a center-island, cabinets of matte white lacquer, and appliances from Miele, Sub Zero, and Wolf. Master bathrooms feature marble flooring, a marble-surround soaking tub, and a separate oversized shower with stainless steel penny tile flooring, marble stone slab seating, and a custom niche shelving of solid oak. They also include glass mosaic tiles, which stretch to the ceiling, and double sink vanities with an illuminated medicine cabinet.

Apartments have the Siedle 611 Series Fiber Optic Security System, that includes a color-screen monitor intercom and one-key access via key-card.