No one says you have to sign a company’s inhouse created contract. If you are incorporated, you can present your own contract. It pays to spend a little money to have a decent ‘generic’ contract drafted, fair to your client and to yourself. As to insurance, well of course if you are an independent contractor you will carry liability insurance, which will cost you about 1500 per year. That is a standard insurance policy for corp to corp work, a normal small business expense. Non-disclosure agreements are typical too, but non-competes can be fought in court and nullified, so write your own non-compete as part of your agreement.
If your husband signed an agreement to work on a Canadian project, then got upset when he got paid in Canadian dollars, I think it’s time he went back to work as an employee. Thinking you’ll be paid in US dollars while working on a foreign project is just jingoistic and naive.