Does your thief get his stronghold after defeating Mae'Var or what?

DUH!!!!!
Make sure you have the proof that Renal Bloodscap wants before you waste Mae'var.
Edwin will assist you with this and once done, report back to Renal.You'll then be the new proud owner of the thief stronghold!!

Just make sure that when you do get it, you keep VERY CLOSE TRACK of when the quotamaster is coming and make sure you pay him when you need to. Otherwise you couled lose it. He's worse than the Tax Office...