Apartment's pictures lie a little bit: it wasn't so clean as we expected, and absolutely not well furnished; many missing cutlery, mismatched plates and no drying rack (but as Shamir said we can of course use chairs, instead...), however we used a hair-dryier because even if we we found a fan-heater in a wardrobe, its plug was dangerously broken.
Shamir and his wife are kind people, they waited for us two hours at check-in time because our flight landed very late, but it wasn't our fault, honestly.
In any case we expected more flexibility with the check-out time as our flight departed at 17:00, check-out was at 11:00 and we asked them to keep our heavy baggages about 1 hour as we have two babies and bringing around baggages could have been very unconfortable. They said they could have done that, but only if we paid 10£ an hour (!). We said thanks, however, but we found the same service at the station, but 6£ for 3 hours...
About the area, there are lot of ethnic shops and if you want to go out for shopping, this is definitely not the right place. Islington is much better and only 1km far. It is very well connected however, but I do not suggest to go to King's cross to families with babies or kids. More than 950€ for 4 days is too much money for what you will find, in my opinion.