After 18 years as an art dealer, David Leonardis (who says he’s done little business for the last four months) is closing his eponymous gallery and selling his inventory of 1,000 pieces by artists ranging from outsider Howard Finster to art-world provocateur Mark Kostabi at 70 percent off. Fri 6/18-Sat 6/19 6-10 PM, 1346 N. Paulina, 312-863-9045.