Translation of rental in Spanish

So you have taken a German course in the Ghoete Institute. Well, I certainly learned something with you, and your German is already a lot better than last time. I think we really did it.
I would gladly be your friend, but I must admit that I have little time for learning because of my work. Maybe we can talk now and see how it goes. If it goes well I can return home earlier.
First, let me thank you for your answer. And how can I support you further? I'd be very happy about it if we could both help in each other in learning Spanish. 'Tandem' learning beats all other methods.