The biggest obstacle for me was getting the keys to the building to work. The locks are very old and it generally took a couple of minutes of fiddling with the keys to get back in.
An English-language person was not available to help us check in. This made it a bit harder to figure out how things worked and we missed out on some of the benefits.
No power adapter was provided for my US-based appliances - I had to go out and buy one.
The street is a bit louder than average.
Aside from these issues, the place is really outstanding, charming, and in an incredible location!