New here- how to verify content sellers?

just found this sub and it seems great. I'm wondering if anyone that's selling content is actually real and will actually follow up on the agreements... I'm looking for a custom video if it matters

Does anyone have any tips on how to verify that someone is legit?

Do people typically pay after receiving the content or before? can see how this just shifts the risk and sure lots of dudes are just looking for free stuff, so I can understand why women don't like this set up

Been burned a couple times, would rather not waste anymore money on scammers