I stayed at Aleksander's apartment with my parents and my two sisters. We were more than happy with the stay and would definitely come back next time.
The apartment was big enough for the 5 of us with it's two bedrooms sleeping two each and a pullout sofa. Thanks to the comfortable sitting area in the kitchen there was no need to reorganize the sofa every day. We could just hang out around the table there.
The fridge and freezer were stacked with all kinds of delicious treats and we had a hard time trying to finish all the food Aleksander had organised for us. He even organized a phone with a lot of getting around apps for London and free data on it for us too use so we didn't have to book any expensive data plans on our own phones, which was soso helpful!
The location is great. Vicotria station is in walking distance (or you can just get on the tube at Pimlico which is even closer for everyone who doesn't like to walk too far). There is a bunch of bars, pubs and restaurants near by as well.

Thank you again, Aleksander, for being such a welcoming host!