Ian is a superb host and very kind-hearted-gentleman. He is quick in responding so you should assume if you don't hear from him, it's likely that something is wrong on your side, not him!
His place is a 5-star accomodation fully equipped with everything you would need. Very spacious and well-designed. My 78 year-old mum and I loved cooking in the kitchen especially.
Speaking of my aged mum, she had no trouble climbing two flights of stairs. It is not as bad as one can tend to imagine. The only time we wanted a lift was at check-in/out when we were carrying heavy suitcases.
My stay was during the first week of Wimbledon Championship. I was lucky to have secured Ian's place back in February as all the "conventional" hotels were already sold out and airbnb's filling up fast.
My word of advice.
Don't waste too much time to compare with others when you find Ian's place available. It's surely to be gone quickly during the fortnight of the Championship! It may seem expensive (but others will be just as so), nevertheless you will get your money's worth (or even more).
I will definitely recommend this place, and will stay if I ever travel to London again.