A: It is unclear what your exact question is. Unless illegal or unconconscionable, anything can be agreed to in a contract. Enforcing the agreement may require litigation. If you are asking if the clause is a valid one, it could be. If you are asking what to do if the landlord did not honor it, you may need to sue. If you are asking if this is standard and was not in the contract, the answer is no. You cannot assume it is.
Hope this helps some. Contact me if you would like a consultation specifically on this issue.