I do not recall seeing anything about the owner being a smoker in the description before I booked. Also, there are a lot of rules that get read to you when you first arrive. Finally, the toilet situation is not really acceptable. I expect to be able to use a toilet right after someone else and not be faced with a toilet that won't flush. She said "I'm getting this fixed soon", but it clearly has been like this for years, because the bathroom and decor is years old.
Maggi is doubtless a lovely person, the flat was very convenient for buses and 10 minutes from Highbury-Islington tube station, 15 from Angel. If you're a smoker: probably OK.
I am unlikely to book here again. I was glad to leave early because I had to depart a day early due to work.