My local GS, has a range in their back room. They had a used P9s in there in 9mm I want(ed) to buy, it was clearly a used gun; in ~75% shape. They let me dry fire it, tear it apart on the counter to look inside. I then offered to buy a few boxes of ammo to try it on their range, paying for the ammo, and the range fee. And they wouldn't let me.
Why? It's a used gun, it's not in perfect condition...I'm paying for everything. What's it going to hurt?
Yeah that crap sucks...that Mauser I bought "worked fine" in the store. Dry firing it and everything seemed to be fine, then when I took it to the range I found out that the firing pin was worn down and wouldn't make contact with the primer, so I ended up having to dump about $30 into it right off the bat for a new firing pin. It works fine now, but it's freaking annoying to buy a weapon and have it not work first thing.