not sure if you are joking, but...
didn't they reduce it to a limit of 1 of the same game per year?
A BB rep on their forums said it was 3 but they've been known to be wrong before. Either way, I think it's basically a pattern of abuse that will get you banned. The computer won't block the transaction.
Also,strait edge follower likes to brag a lot about his BB trade in exploits so take his post with a grain of salt.