[TowerTalk] Roof mounted tower

[Steve]

I'm considering installing a roof mounted tower such as those sold by
Glen Martin Engineering. It seems likely that I'll sell this house in a 
few years and, at that time, remove the tower. Following removal of the 
tower, what will be the condition of the shingles at the tower's 
mounting points? What will I have to do to repair the roof to make it 
acceptable to a potential home buyer?

Thanks.

Steve