The biggest problem with cell boosters is, they need a good signal coming into the antenna to work.
For the majority of situations, the customer is wanting a booster because there is poor signal in the area. Well, that means a very tall mast to put a high gain antenna on (and precise alignment to the tower) if there is any chance for it to help at all. And if it still can't get a good enough signal then...
The training for Wilson and Sure Call both say they want to see -90dB to -70dB on the incoming antenna. That is a strong signal for 4G/mobile.
So for most people who don't understand this mechanic, they rush out and buy these $600-$1,000 boosters thinking it is going to fix their problems. When the reality is, they were not meant to do this very thing you expect them to.

These devices shine where people are in a big metal building, with almost no signal inside but strong signal outside. THAT is what these devices were meant for.