As we were travelling to Prague, we received a message with the check-in details and a request for a substantial deposit (apparently to protect the tech in the apartment?). As we were en route and not really in a position to argue at that point, we paid the deposit. While it has now been refunded, we're completely baffled about why this happened - there is nothing at all about this in the listing, and Expedia have nothing to say on the matter. I think it's important to raise it here in case it happens to someone else and they're unable to pay it. Luckily we were able to but I think it's really poor not to be transparent in the listing - and only to mention it the day before we arrived. Oddly, I can't see any other reviews mentioning this charge so I don't know if it was a mistake? There really wasn't any tech other than a TV!
Other than that, the apartment was fine. It was very clean, the location is excellent and the view from the apartment window onto the castle (not a river view!) is absolutely stunning, especially at night. The bed was comfortable and it was nice to have a sofa and coffee table. Check in was smooth.
As others say, there are lots of steps and no elevator (fine for us but others might struggle) and a shower curtain would be good. It would also be helpful to provide some coffee pods for the coffee machines as they're not very easy to find.