I am lucky in that everyone I have dealt with has been golden and all transacations to this date have gone through without a problem. Some people are not so fortunate.
If you have dealings with somebody for an airgun related purchase and feel the deal has gone south there is a mechanism in place to give feedback.
After all attempts to solve the problem has failed and communication has broken down , that is when a post on the Board of Inquiry is needed. The Yellow Forum Board of Inquiry is a feeback mechanism anyone can use to check on previous deals of fellow airgunners. I suggest you check it before doing any deals and it may save you some headaches.
In turn be sure to post postive feedback as well and ask the people you have successful dealings with to do like wise