Wantto know what to ask contractor when gives me a estemet on my roof. I think I found an answer. 1. License 2. Insurance ( Make sure its for roofing or else you will pay in the end if his work fails and his insurance is for handyman or carpenter ) 3. How long he has been in buisness 4. Ask if he personally does the work, or if he has a crew 5. Ask if he will be present on the job 6. Ask type of warranty 7. Ask what type shingle he uses (owens corning, Certainteed etc ) what are the advantages of this product 8. Ask how much ventilation is needed and what product he uses 9. Make sure he puts new flashings up and not re-uses old ones 10. Ask for any discounts/promotions his company runs Most dimensional shingles offer a lifetime warranty on shingle failure which must be installed to manufacture specifications, if it is not followed they will deny your claim so make sure on what product he uses he follows the specifications. also he can’t guarantee you a lifetime roof, he can only guarantee his workmanship for a certain period of time, dont fall for the “i guarantee this roof for life line” its only guaranteed if its followed by manufacture specs and like I said to a T . .