(blog updated below)
There may be an unusually large number of people using personal digit assistants (PDAs) in the Loop on Thursday evening, but they won’t be checking their e-mail or the sports scores. They will be buying condos.

The developer American Invsco, which is converting the 47-story apartment high-rise at 200 North Dearborn Street to condos, hopes to sell all of the building’s 270-plus units on Thursday night. The venue will be an innovative PDA-based sale that Arnold Schepel, the company’s marketing vice president, says is designed to “level the playing field.”

Although American Invsco has been advertising and showing the condos since May, no one has yet been allowed to buy (other than the building’s existing renters, who by law get first crack at their units). But at 7 p.m. tomorrow, up to 500 potential buyers, all holding PDAs handed out by American Invsco, get an equal chance to put dibs on the condos they want.

“You don’t come in to a sales center and find out that ‘these are the units that are already sold, but we still have these other units,'” Schepel says. “Everything is available that night.” Should allthe condos sell, American Invsco won’t have to invest in a sales center and staff, nor will it have to bear the costs of carrying the units until they do sell.

American Invsco is calling the sale its One Night Only Best Price Event, and true to the name, prices on anything not sold that night go up ten percent the next day. For the PDA sale, condos in the building are priced from $195,000 for a 570-square-foot studio to $482,100 for a 1,205-square-foot two-bedroom, two-bath condo. Schepel says that renters have already spoken for about 10 percent of the building’s 308 units. Floor plans, pricing, and other details of the sale are at 200ndearborn.com.

For the roughly 275 units that are still available, Schepel says, about 800 people have stopped by to take a look in advance of the sale. He has 500 PDAs at the ready. And if more than 500 people show up tomorrow? “I don’t know what we’ll do,” he says. “We don’t expect more than that.” Buyers must return the PDAs after the sale; American Invsco will use them to sell other buildings in the future.

Friday, July 13 update: Schepel states that 102 of the condos sold, the remaining are now raised 10% in price.