Most of what you want to know should be in your lease.
If I were you, I'd try to comply with your landloard's needs. If she's selling for financial reasons, she could end up in foreclosure, and then you'll have no chance of staying in your home. If, on the other hand, you show your place in good condition, and she is able to find a buyer in this terrible housing market, the next owner may see you as an asset to the building, and want you to stay. It's not fun for a landloard to look for a tenant.