Back in 2009, my insurance company (Progressive) sent me a letter saying that I needed to replace my roof or they were dropping my coverage. Instead of replacing the roof, I just switched insurance companies to State Farm. In hindsight, the first insurance company was right as within about a year the roof started to leak.
Anyways, one thing you might want to consider is getting a quote on a metal roof. The metal roofing material will probably be bit more expensive, but I believe metal can be put over two layers of shingles so you might be able to save the cost of the tear off causing the metal roof to be not that much more than shingle. The real savings with a metal roof come in A) lower insurance premiums because of hail resistance, and B) not having to replace it 15-20 years from now.
When I was replacing my roof seven years ago, I got a couple quotes right in the $6,600 range for putting on shingles with a standard tear off. My roof was 22 squares with a fairly low pitch, so scaling that up to 46 squares and adjusting for inflation over the past seven years that works out to a smidgen over $20,000. The house was in Lafayette, Indiana, so probably comparable to Pittsburgh.