Suggestion...check with the SUB contractors to make sure they are paying their bills to the suppliers and their men. One of my friends had an addition to her home put in and when the contractor left town suddenly, she found that the workers put a lien on her house. She wound up paying for it twice. She learned an expensive lesson. After that, when she had to have some work done on her house, she had the contractor order the materials, she went down and paid for them and had them sent to HER house, which a lot of the previous supplies weren't. And she did remember to question the men every Friday if or if not had they been paid!! And I think she questioned the state board as to the second contractor's record in his previous jobs.
That's another thing most folks never think of. You get his number, which you really should have on the contract, then you can check it out easily enough. Should anyone "not remember it but I'll get back to you" or not have a license plate on their truck, or can't remember their new phone number, any one of those should be red flags that should be noticed and acted on.
Sigh...you can't trust anyone it seems.
Plus, before signing a contract, ask for the names and addresses of everyone they had worked for in the last 3 years or so. We did that when we had a new roof put on, but only got part of the "lookers" to comply with that. The one we chose gave us not only names and addresses, he put down the total footage of each roof and what it was made of, tile, concrete, etc. Really did have a good record, since we did check with a few of them.