It depends on how it was set up by the lawyer. Rent to own? Installment sale? You'll need to ask the lawyer about this. They'll know what forms if any, need to be issued for your situation.
Just curious.
They are responsible for everything (repairs, taxes, etc.) until it's paid in full.
Then who's responsible for those things after it's paid off?
Keep this in mind too.
In my experience I have never seen a "rent to own" or an installment sale succeed. Not ever. Generally, the seller ends up foreclosing on the property. So keep all your paperwork.