The apartment has a wonderful location, directly opposite the Common. It's a 5 min walk to the Clapham Common tube station, and several buses run nearby, so traveling into London is easy. Good supermarkets and restaurants are also nearby - just a few minutes walk. The apartment worked well for us (my wife and I plus our two kids, 9 & 10). The kids shared the double bed in the front room and we slept in the double bed in the back room. The kitchen is not massive, but more than adequate. The living/dining room is very nice. Bath/shower/toilet are at the back of the apartment - which works well. The apartment is on the top floor - so a little exercise each day walking up and down. Parking outside seemed to be controlled, but as we didn't have a car, this was not an issue. The only negative is that the traffic outside the house is fairly heavy, so there is some road noise. It didn't bug us, although the kids mentioned that they were disturbed once or twice when police cars with their sirens on drove past. If you are a very light sleeper, this might be an issue.
Clare was great - she left us some food and drink in the fridge - which was much appreciated as we arrived late and it was raining. Clare was very friendly. She was also very responsive when we had questions but otherwise left us to our own devices. All in all a great stay. Would definitely stay there again.