they typically want to wire you money or pay with a bogus check, but the biggest telltale sign is when someone other than them is going to take possession or pick it up. If they say something like "I'm going to pay and then send someone to pick it up," that's a scam. If you are selling it to someone you can verify is the actual buyer and work with them in person you won't have an issue. You can also go to the Utah State Tax Commission and print out the generic bill of sale and fill it out and have both of you sign it. That will show that ownership has transferred in case something happens the moment after they take possession.

https://tax.utah.gov/forms/current/tc-843.pdf