John--Thats a tough call but there is simply no excuse for not staying in touch. If it were me i'd go another day and then repost it for sale. If a check arrives i would send it back with a letter stating you didn't know what happened to him. It will likely get messy but you did nothing wrong. This is my opinion cause you asked. You may handle it your own way because its your gun. Everything i have sold and bought here involved very good communication. I always request a phone number and prefer a phone call to discuss things in person via phone. I'll repeat, communication is very very important. I think you have done your part. Good luck friend. I feel for you.