Suspicious Purchase On Facebook Marketplace

Im in Colorado! I’m selling some nice shoes I wore a few times on Facebook. I had a reasonably sketchy Facebook user reach out and ask if I had really worn out shoes that he could purchase for above retail value. Then he asked if I’d wear them for a week and the same socks. Then he’d pay me 100 for the socks too. He is trying to get me to ask for a higher price as well and wants me to wear them when we meetup and take them off at the meetup. I have no idea why anything about selling old shoes and socks would be illegal but it feels like one of those traps people trick pedos into. He even sent me $100 on Venmo to “prove” he’d pay for them. A few quick googles didn’t reveal anything but the whole things is fishy and I want to make sure I’m not doing something stupid and illegal by selling some shoes I was gonna throw away anyways.