I enjoyed the location of the apartment building and think the place has great promise. It was located to nearby places to eat and the train station. The area was safe and clean. I do recommend updating the listing to make sure it clearly states that the unit is a basement unit, specially for out of towners. The steep stairs to get to the basement may not everyone cup of tea.
I really thought your communication once i was in the place was very quick which i appreciated. I would suggest you plan out the stay a bit better depending on season to ensure the visitor does not have to reach out too much if all the amenities are already in place, such as towels, soap, a way to turn on the stove, a way to connect with you regarding heat, etc. This will limit the interaction necessary with you for just basic amenities.
The last suggestion i have is to try to trust your visitor. If you hear something from your visitor that does not sound right, find a way to verify rather than assume they are lying. I understand it is difficult to trust strangers, but we place equal trust in you and the details in the listing to book your place. It was very disappointing to me when i presented a rat problem at your unit and you took the road of disbelieve rather than ensure your place is free of rodents.
I do wish that you improve your place and list the items necessary so that you can continue to book it as it is in a nice location.