Lease states landlord is responsible for "gas utility"

If you have a disagreement with your landlord about a lease term, your remedy is to sue them. They are going to argue that you waived your rights by paying the "gas utility" charges for the last 2 1/2 years, and that having waived your rights you cannot demand that they reimburse you. That argument is ridiculous. You are asserting it now, and it is a reasonable position to take that having renegotiated a lease three times that says landlord pays "gas utility" the lease means exactly what it says. Contracts are always construed against the drafter. So you can sit down and calculate exactly how much you have paid in the last 28 months for "gas utility" and write a demand letter. If they don't pay it, and the value is less than $5K, the fastest thing you can do is take them to small claims. This is not going to enhance your relationship with your landlord, so be prepared for them to terminate your rental agreement in six months when your lease is up. Elizabeth Powell

Take them to small claims! You can hire a new lawyer for less money but you can also represent yourself at small claims-- that is what it's there for. Don't let them scare you!