Fencer

A person who buys stolen goods from thieves

Can also be referred to as a middle man

The thief got rid of his hot items at the fencer

(A hot item is stolen, usually asked by buyers if an item is hot before buying to make sure what they actually pay for)

ib4

ib4 means in before

Which you can also read about here: urbandictionary.com/define.php?term=in%20before

ib4 they lock up the rooms then lets get out!