Re: the original question about getting nicked after checking out. I've not heard of that & not sure how they could do it after you've checked out. Not saying it can't be done, but not heard of it. More the norm to be asked for id at check-in & possibly get hit w/ rack rate if you don't have it.
Also, check the rate rules. If there is an exclusion for sub-contractors (which happens w/ some gov't rates), it should say it in there & so you'd know in advance if that line was going to work or not.
Cheers.