The biggest problem I see is that these guys watch a video and think, "how hard can that be?" So then they start pricing spray guns and think, "Wow, that one is $800 and this purple one is only $20. They looks the same so . . ." Then there is the sticker shock on paint and the same mentality kicks in, "Paint is paint so why not buy the cheaper one?"
Once they begin to paint their car multiple problems happen and it is then that they seek advice. Only it's too late because they have already wasted so much time and money on their "budget paint job."
When you tell them their gun is junk, their compressor too small, the paint they bought is garbage, etc. they get mad at YOU!