These taxes have become standard development tools in Missouri. St. Louis has authorized both a CID and a TDD for the midtown City Foundry development, and plans to do the same for a proposed Major League Soccer stadium.

In Kansas City, the four-star Intercontinental Hotel cited torn wallpaper and stained carpet to win a blight designation, which let it set up a CID to pay for a $16 million renovation. Instead of paying for new carpeting themselves, the hotel owners charge a 1 percent tax that guests don’t see until checkout.

Similarly, owners of the Marriott Grand in downtown St. Louis created a CID and TDD in 2010 to essentially pay the hotel’s mortgage.

Transparency is a big problem with these districts. State Auditor Nicole Galloway found last year that the Department of Revenue didn’t adequately track CID boundaries, and that many districts failed to file financial reports.

By law, merchants in a TDD are supposed to post a notice near the cash register warning customers of the extra sales tax. Few do.