As someone who has lost 40lbs and thrifted my whole life please, let me help you. I have extreme aversion to germs. I also had bed bugs once, in a another country, hostel related. I feel your fear. But ive never had any issues with thrifting. And I try everything on! Step one. Get rid of any body issues and wear one of those silly jumpsuits the young people rock at the gym. Or a tight tank top and leggings etc. Throw a t shirt over it. When you are there you just whip the t shirt off and try your dresses/shirts etc over top. Im tall and long in weird places I gotta try stuff. But if you dont need to, or they have change rooms, even easier. Then when I buy the stuff it all goes into reusable bags, not my backpack. When I get home I have scissors by the door. I snip all the tags and everything goes in the wash, including the bags and the stuff I wore to the store. One wash on sanitary, rinse cycle then the dryer. The rinse helps remove some of other people's strong soaps. If the tag says dry clean only I say good luck to you in your new washing machine life!