These units are in a NEZ zone [[Neighborhood Enterprise Zone), right?

So they have 15 years of greatly reduced taxes... until the NEZ expires. Here's a copy/paste [[Detroit News, Feb. 13, 2018) about a Corktown resident who had their NEZ expire...

"Nearly all new Detroit condo projects have secured or are attempting to get NEZs, a process that requires city and state sign-offs.

However, most NEZs expire after 15 years — and there are no extensions. Once the expiration date comes, condo owners face Detroit's full millage rates, which can add several thousands of dollars a year to tax bills.

"Even if people know [[the expiration) is coming, it can create a big challenge near the end of the NEZ certificate term when an owner has to face upcoming drastically higher property taxes," said attorney Richard Barr of Honigman Miller Schwartz and Cohn in Detroit, a real estate tax expert.

"The expiration is a big problem, especially with increasing property values and assessments," he said. "We don't want existing owners to be shocked when their bills go up so much. And we also don't want them to be moving out two or three years before the NEZ expires because they're afraid a potential purchaser of their home is going to see the upcoming property tax increase and say 'I can't afford it.' "

A buyer of a $625,000 condo in Detroit's trendy Corktown neighborhood recently experienced an NEZ expiration — and a dramatic tax surge.

The buyer, who hailed from New York, bought the 6,000-square-foot unit when the building's NEZ was in effect and the unit's annual taxes were about $2,000. But the NEZ soon expired and the condo's tax bill shot up to $29,000, according to agent Matt O'Laughlin of the Loft Warehouse.

The condo owner is in the process of appealing the tax assessment with the city, O'Laughlin said."