Rubber Roof Estimate Help

[Amanda Sokol]

I am hoping someone can help me....Attached is an estimate for a rubber roof. I honestly no zero about the product. I have only done houses with shingle roofs. I was told by two roofers that membrane or rubber roof is my only option because of the roof pitch. There are 2 pitches less than 4". There is also a brick parapet running through the middle that acts as a firewall between the four units (it is a quadplex). The attached estimate looks good to me, but does anyone have experience with it, GAF? I did ask about if all new sheeting is needed, but he doesn't think it is. If I need all new sheeting it would be an additional $2900

Below is what his email said...

The roofing system we quoted you on is a very dependable multilayer built up rubber roof. If you wanted to save some money we could install a TPO (white) membrane over insulation. That would be 12,700. with same warranty.

Please let me know what you guys think or if there are additional questions I should be asking.

Thanks!

Amanda