Ya, what Augie said.
We constantly have customers who show up with this fixyture or that one and want them hung, anything from a custom built antler fixture to a huge wrought irom affair. Most are handmade and contain NO UL sticker. We refuse to hang them and will install a plastic keyless fixture instead, knowing full well that the customer will hang the fixture themselves or hire someone who will after the final inspection. As long as I didn't install it, more power to them. some will say that attitude sucks but I gotta CMA.