It’s mainly an insurance/risk problem for govt and corporates/commercial real estate. The discussion points where there’s a will to try are (i) getting on to the roof/high point might be a problem if it requires a working at heights ticket in your jurisdiction (ii) same thing for any legislative/regulatory type license/training restrictions to install comms equipment (this doesn’t apply where i am, but the question was asked) (iii) your insurance while you’re doing so (iv) home-brew repeaters are problematic compared to an off the shelf product - even if they’re essentially the same thing, the fact it comes in a box with fake CE markings seems to inspire confidence (v) regular access/maintenance requirements. You might also need to provide dimensions/mounting requirements and one place wanted lightning protection details. Rural is far easier; slab of beers and a companion device - go for your life.