Asking money for wifi is something very old fashioned, but if you do please make sure it works well! And for the hotel management I like to advice you to give some more freedom to your employees, trust them and give them the responsibilities to act accordingly. I booked two rooms for two nights but due to an emergency my colleague couldn't join, I didn't even try to gain back any money for the last minute cancelled second room but it would have been a nice gesture if you show some empathy ore compensate with an upgrade/free internet or whatever instead of charging for internet which is disconnecting all the time and starting a discussion with your visitor about nothing.