Pros: Location is really convenient, 5-7 minutes walking distance from Kings Cross station, many shops etc nearby, easy to locate. Checking in earlier than stated time was also possible. Host is responsive to all queries and replies quickly. There is quite a lot of privacy given. Kitchen is quite usuable, and the sitting area is cosy. Cleanliness is generally fine if you are not looking to stay long.
Cons: There is no lock on your own room door so safety is an issue. If you have heavy luggage, there is no lift so you need to lug it up yourself up 5 flights of spiral staircase. The host lives on site in the other room, so listing may not be entirely clear that the apartment is entirely yours to rent. The toilet is not bad, but the water pressure for the shower is really low.