Nadja is a great host, I did not have any complications with her and I'm sure you'll do the same.
About the flat: This is a great little flat located perfectly for getting around with the subway. If you plan on staying with the car you'll have a bad time unless you in possession of some kind of parking permit or plan on driving a lot. Parking costs around 15£ every 4 hours....
other than that, great and kind host who will take good care of you and a lovely little flat await you!