 Smash here for Matt Horn and Landmark Realty. 618-466-1513. Matt has about 30 people in the office ready to serve your real estate needs. If you're looking to sell, you've got to list with a leader, Matt Horn. If you're looking to buy, you want to make sure you've got people who know how to do the paperwork. Landmark Realty. And believe it or not, this is a magnificent time to buy or sell real estate.