The landlord can’t charge more than what he agreed to in the lease and section 8 agreement. Those contracts are legally binding. Verbal agreements are not. He can’t evict you for not paying extra.
That being said, agreeing to pay more on the side would be a violation of your voucher terms and get you into trouble if he has proof that you agreed to it or already paid some. If that’s the case, go to the caseworker ASAP and be honest. Explain that you were undergoing cancer treatment and under a tremendous amount of stress and didn’t understand everything. Hopefully, they will be sympathetic to your situation.
But the landlord won’t be. He’s going to be mad that he’s not getting his extra money and will be looking for a reason to get rid of you. Don’t give him one. Be a model tenant and don’t violate any lease terms in the slightest. With luck, he’ll get over it and keep you at the end of the lease because you’ve been a good tenant (but will probably raise the rent 5% + CPI for your area). If not, you’ll have to find a new place, but then you’ll be more prepared and won’t have to rush the process.
