Spike Jones, here's how it works.
I have some brass to give away, someone tells me that they want it.
I give it to them, then that person is expected to put something up for free to whomever wants it.
There is a level of trust here. You can always look at someone's feedback and see what kind of person they are.
If you want the HI-VIZ sight and daddyusmaximus lives in another part of the sate, it is reasonable to think that he is willing to ship it to your house for free, as opposed to driving half way across the state to hand it to you in person. You have to trust him.
I think you may be a little too paranoid to participate in this thread.
So easy a caveman can do it.