Jay's parents' house is very nice and a great value. It's situated in a safe neighborhood, very close to public transportation. The room I stayed in with my children was large and comfortable. Jay's parents are lovely people, very kind and accommodating. From their house we were able to walk to the metro in less than 10 mins, and the center of London was about 20-25 mins from there. There are also many busses that stop right by the house and several shops to buy groceries and anything else you might need close by as well.
A couple things to note:
-The picture on Airbnb is not exactly accurate. The room has 2 twin beds (I think they can be pushed together to make 1 large bed - we were comfortable, but I should note that they were very firm mattresses. Also, the 3rd "bed" was actually a recliner with a mattress on top. it was too short for my 13 yr old and she would have had to sleep on a 30 degree slant, so we ended up making a pallet on the floor, which worked fine for us. But just something to keep in mind if there are 3 adults in your group.
-Also, if you are sensitive to noise at night, you should know that the room is right on the busy road, which is very loud - sirens drive by most nights quite late. We visited during a heat wave so we had to keep our windows open to cool off the room, but this probably would not be as big of a problem if we could have closed the windows.
Even with those issues, the place is great value for the price and we would definitely stay again.