Great stay in London! The host gave us all the explanations to access the apartment and everything was fine. It's very near Victoria station, which is like a node station for subway, bus and train, so you can go everywhere in public transport (which btw is one of the best i've seen in my life).
Three cons: 1) we don't know why, the central heat would turn off during the night so we had a little cold, it happened everyy nigt except the first. 2) the dryer machine didn't dry at all, I paid and used it twice in a row and didn't work, so I had to hang all oir clothes along the apartment to dry them, without heat in it! 3) The bed is smaller than a queen size, so if you're a couple you may find it a little small, but for only one it should be fine.

I think in the overall it was a very good stay in good place. Thanks to Alessandro!