The average price for condominiums in Prospect Heights is $621 per square foot, according to Miller Samuel.

“If our units would have been smaller, the price per square foot would have been even higher,” said Brendan Aguayo, who is representing 650 Bergen Street as a senior vice president and managing director of Terra Development Marketing.

Because the building offers few amenities, requiring no salary for a doorman or upkeep for an elevator, Mr. Drukker is able to keep the monthly common charges low. For the three-bedroom, for example, the monthly common charge is $247. And because the buildings are three stories high, the units have low real estate taxes; the three-bedroom has an estimated tax bill of just $420 a month.

The math is very different at the seven-story Hello Washington, a new condominium at 618 Washington Avenue in Prospect Heights, where the units, all two-bedrooms, are priced at an average of $872 a square foot, according to listings on Streeteasy. The monthly tax bill for a $935,000 two-bedroom there is $596 and the monthly common charge is $538.

The city calculates its real estate taxes for new residential condominiums of up to three stories by assessing them at 6 percent of their market value, based on sales prices. For new condominium buildings with more than three stories, the city assessment is 45 percent of the apartment’s rental market value, which typically results in a much higher tax bill, said Paul J. Korngold, a partner at the law firm Tuchman, Korngold, Weiss, Liebman & Gelles.

“This is a luxury building and the apartments aren’t cheap,” Mr. Drukker said. “So if you also had to pay $15,000 a year in additional costs, it would be much harder for me to sell the apartments.”