Always read the small print Audrey, especially in contracts, even more so when it is with an agency. Never sign a contract without thouroughly reading it and demanding a copy for yourself with ALL signatures on it.
Never trust them. Ever.
And always scrutinize your paycheck. Look up what the numbers mean. Get an explanation at your union (if you are member of one, always advisable because they have a nice legal department with not-so-nice lawyers).
They are out there, trying to ripp you off.

Hmm. Have I pressed the subject of paranoia well enough now ?