The experience was great! To be honest, it was over my expectations! The room and the flat itself were really cosy, well maintained and had everything I needed - including iron, towels, washing machine, even washing powder!
Talking about Kai - he was a great host. He was very kind to wait for me even though my flight was late and I got to the place at 2am! Appart from that, he showed me around the flat, told me all the details I had to know, sent me a list of shops nearby, stops for nearest busses, tubes and a lot of othe useful things. If I ever come back to London again, I am sure that Kai will be the first person I will try to contact for the accomodation.