I just paid for my maint guy to do this. Cost a “fortune” IMHO, about $150. I told him up front that the reviews of the antenna bracket indicated it was difficult to put up, so I wanted them to review how to install, before getting on roof top.
Of course, he was busy and sent over a jack leg who gets on roof top, having never ever looked at the instructions or the kit, he can’t figure it out (he had not looked) so I ended up paying for 3 hours of some fool trying to read instructions. If I had not forewarned him of the issue, it would kind of been ok.
I just bring this up, since my estimate was about an hour job, max and it took a whole lot longer.
If I did not need my man, and if he had not done so much for me in the past, I would have not paid that much.
Just make sure your guy understands. I would contact a roofing company or maybe the cable company. I had no luck in my area looking for antenna intstallers!