Jason's flat is lovely. I spent 2 days there with my sister and a friend, the apartment is big enough to host 4 people and it comes fully equipped with kitchen's appliances and utensils, that made it possible for us to cook a traditional English Sunday roast. The apartment is less than 5min away from Clapham Junction, which makes it very easy to reach both central London and Gatwick Airport by train. There are a lot of restaurants, shops, supermarkets and pubs in the area, so you can go out for dinner or simply stay in and make your own dinner, just like we did. The place was so lovely, we honestly didn't want to leave. Jason was absolutely wonderful to us, he fixed a minor issue with the heating as soon as we contacted him and went above and beyond to make sure we had everything we could have needed.
The cafeteria downstairs is an added bonus.
I strongly recommend booking this place, you will not regret it.