At the Tucson Gem and Mineral show in February, which is basically a
retail show, the city tax person gives you a form at the beginning
of the show and comes around near the end of the show to collect the
taxes you should have been collecting on your sales. They have
always been polite and patient and respectful of conversations with
customers. They stand and wait until you are free to talk to them.
Although you will not leave the show owing city tax.