Just did a residential house of a gentleman that I met at Scouts Canada, when our kids where members, years ago.

Anyway we got talking and he mentioned to me that out of the 4 estimates he got two of the company's where not in good standing with WCB (Work Safe B.C.) This could  be big trouble for the home owner. Work Safe is allowed to come after owner for any WCB payments on Labor for your re-roof project. And God forbid if someone got hurt that could cause home owner big problems. You can confirm if your contractor is in good standing by going to WORK SAFE BC.COM and follow links to get a clearance letter.