My 30k LOC through RBC was closed (without my knowledge or consent) because in Jan, I paid off the balance in full when my house was refinanced.

The contract states "I'm not allowed to rent the property without his written consent during the contract period" I guess I thought screening renters would be okay. 

Also, I have read that the company that owns someone's mortgage has to, in some cases, consent to the LLC becoming the "owner."

You've got to get consent from EVERY lienholder to pick it up with clear title, and they are all going to want to get paid in full, but might accept getting paid in part depending on xyzabc. 

He tore down the house that was supposed to be remodeled and made it a new construction project without our knowledge and consent. 

I'm guessing its not legal to lock him out without his consent, being that he is still currently on the lease. but I'm not a lawyer.

I'm guessing they sublet to the meth dealer without your consent, so you probably had recourse to evict them at that point.  

(I sure already have their consent signature).Thank you!

It's nothing more than consenting adults engaging in commerce. 

The broker would also need to get written consent from buyer and seller to act as an intermediary.