@Anna9372
I live in a fairly central part of London and don't have a problem with WiFi connection/speed (although I did recently have one guest who complained about it regardless).
However, I would say that, if something is a 'sore spot', which in my case might be that one of my rooms is up several flights of stairs, or that another is facing a busy/noisy road, I have found that it's not enough to simply state it in the listing. It should be, but unfortunately people either don't read or read 'selectively', i.e. choose to ignore the bits they don't like.
So, when you know what those sore spots are, make sure to message the guest about it, ideally before you accept their booking (or as soon as they book, if you use instant booking), reminding them of those issues and asking them to confirm they are okay with them.
It's not foolproof, but I've found that it avoids a lot of issues. You might lose a booking here or there (from guests who find fast WiFi particularly important), but better to have no guest than an unhappy one who leaves you a bad review.