Overall we enjoyed our stay with Kasia and Alan. The apartment was exactly as shown on the pictures. Alan explained us a lot about getting around and places to visit while checking us in.
The apt is located in a residential area, about 15 mins away from the city center by transportation. It is on the ground floor, facing the street, so in when the windows are open (there's no airconditioning), it can be a bit loud in the evening and early morning. The bathroom is tiny and we could hardly get in/out of the shower.
The check in was a bit inconvenient for us - the hosts required us to call an hour before we arrive, then to call again by the door while our US cell-phones didn't even work! Also you need to wash and towel-dry your dishes after you use them, wipe the counter, extra towel costs extra and so on. The whole list of house rules they present after you book the apartment (and the cancellation rules are strict, so no way back!) is not quite relaxing and welcoming while you are on vacations.