The careful "consulting all
people involved" verification that you'd jolly-well
better perform before you accept any
paper financial-instrument from anyone, especially if the document is "signed over" to you by the document's original payee!
Performing a two-
party check is vital to maintain your financial integrity, not only because you might not get paid, but also because you could get
hit with a returned-check fee and other legal hassles if the check is either drawn on an account with insufficient finds or is written without the account-owner's authorization.