The latest mansion going up in Winnetka is not a single-family home-even though it looks like one. Instead, the outsize Tudor-style building under construction at 718 Green Bay Road is slated to house 13 condominiums. Myefski Cook Architects designed the building to “fit right in with the look of Winnetka and Glencoe,” says Mary Anne Perrine, a sales agent with Baird & Warner. Apparently it worked: Perrine says at least one wealthy house hunter has mistaken the place for a single-family residence.

When completed in September, the Winngate, which is replacing four small houses, will contain homes ranging from a modest one-bedroom unit to larger condos with sizable terraces concealed between the roof’s eaves. Parking is included; there is a common yard area facing a quiet residential street behind the building.

Buyers have already taken six units. Of the ones remaining, the smallest is a 915-square-foot one-bedroom unit on the first floor facing Green Bay Road that is priced at $435,000. The most expensive is a 1,931-square-footer with three bedrooms on the second floor with two balconies-one facing Green Bay Road-for $855,000.

Illustration: Bondy Studio/Courtesy of Myefski Cook Architects, Inc.