Moboost.I had one do that once. Andre (don’t remember his osa handle anymore) that has the street rod shop over in MWC sold me a gun I really wanted.
Pulled up and looked at it. Handed him a bunch of money. He handed me $50 back. I still have that shoulder breaker. Don’t have the $50 anymore.
I sold him a few Mauser rifles a few years ago. He didn't haggle or anything.