I'm very sorry to say that I would not host this guest again or recommend her. She stayed with her friend one week and at check-in compared the Airbnb system to a hotel service. They damaged a white antique desk and said that I or the cleaner did it ourselves right after they left! She has been unable to express the problem with the shower, only understandable if one was standing under the shower head + taking a shower, which she didn't say. I came twice with another person to check it - of course without taking a shower - and we didn't find any problem, until the next guest explained it simply. The water didn't leak, but splashed out above the shower stall until the holder was screwed twice (thanks to the next guests who finally made it clear). So the problem was that they had to take their showers by holding the shower head with their hands... There was no water clog either, but dirt and hair on the grid - once I cleaned it for them, everything was fine. The washing machine is modern, with a dryer, as the dishwasher is, which other guests found very convenient. The heating and electricity costs are detailed in the description of the apartment and in the rental rules, but they didn't see this and complained heavily. Altogether a very unplesant experience unfortunately.
Thanks Alexey, you've been a great host! You're right, I like bright colours and not too much decorated places :) I have 3 photos in the apartment, one very big and coloured, two b&w, from the exhibition of a professional photographer, also two colourful vases and some brown candles. Definitely not too much decoration, that's what the guests who stayed several months enjoyed! But if you come back, I'll add some more ;)