Mrs. Lee, I'Ve stayed here for almost a week. And I really must leave tomorrow.
Please feel free to stay as long as you want. You know you're always welcome here.
Thank you. You'Ve been so nice to me.
Is there anything else I can do for you before your leave?
No, thanks. You'Ve done a lot for me already. Thank you for everything.
Don't mention it. I'Ve really enjoyed your company.