Builders bring out the stars to introduce new developments.

Playing an inspired set of some of his greatest hits onstage last Thursday in a heated party tent erected on the site where Gary Barnett's new condo building, the Avery, will soon rise, international pop star, Seal, brought a whole new level of glam to the Manhattan residential publicity party scene.

And Seal's star wasn't the only one that studded the night.

Downtown, a party for Leviev Boymelgreen's residential condo project, 20 Pine Street, featured a similarly high profile performance by Grammy winning R&B singer John Legend. It has been well reported that developers have employed actors and athletes to generate buzz about their properties that they hope in turn will translate into brisk sales or leasing.

In its marketing of the Cipriani Club Residences at 55 Wall St., the project's owner the Cipriani Group bagged actor Mickey Rourke and model Naomi Campbell as tenants in order to infuse the project with a celebrity presence.

Now Barnett and Boymelgreen's entry into the music scene represents the latest addition to the overall celebrity trend, which many residential market observers have interpreted is being employed by developers to buffer their projects the effects of a slowly softening condo market.

"It may not translate into direct sales but I think that a lot of people are going to remember how Seal came to play for Gary Barnett and how John Legend played for Leviev Boymelgreen," said Edan Shiboleth, the director of finance and investment for Boymelgreen. "The envelop is definitely getting pushed and having big name artists is the next level."

The Avery, a 274-unit, 32-story condo building on Riverside and 65th Street, is scheduled for completion in 2007. 20 Pine, whose construction is already underway, will have 409 units, nearly 50% of which have already been pre-sold, according to Shiboleth.