Our London trip was a birthday present for my mum. She never went much abroad and it was her first time in GB as well as doing a homestay.
Well, she says she'll always keep it as a great experience. Which is also due to the great hospitality of John and Natalie.
Their house is nice and tidy with a warm, relaxed atmosphere. It's close to public transport and not far out, especially for a city like London. The area is hilly though, but gives you great views as well. Close by there are restaurants & pubs like the "Sparrowhawk".
John was providing good tips to get around and Natalies was caring for us very well, even though having lots of other things to do. The whole family is easy going including Natalies Cousin which we had the pleasure to meet as well.

To put it short, I can highly recommend to stay at their house.