I cannot say enough good things about our experience at Gareth's place.
First - communication is stellar. Paul, Gareth's co-host, responded immediately to every inquiry we had, even before we made the booking. Paul met us at the house the day we arrived in London, exhausted and with an airsick child, and let us in, showed us around, gave us the lay of the neighborhood, left cupcakes on the dining table and then respectfully kept his distance for the remainder of our stay - checking in on us once to make sure we were doing ok. I'm sure if we had needed anything during our week he would have been there helping.
The house was spotlessly clean. There were PLENTY of linens, blankets, extra pillows, towels, extra towels, kitchen towels, hand soap, toilet paper. There are 3 blow dryers, an iron, ironing board and clothes drying rack. The house is very comfortable.
There are two kettles and we used the French press in the kitchen to make coffee every morning of our stay. The kitchen is fully functional and has everything you need to cook meals.
The thing about London is that it doesn't matter too much where you stay as long as you are close to a tube station. The Angel underground station is about a 10 minute walk from Gareth's place. Buses also stop in front of the station constantly. Use an app called Rome2Rio or the London TFL app to plan your routes around town. So getting anywhere is very easy from Angel. King's Cross is one stop on the tube.
The best thing about staying at Carbon House is the neighborhood. We truly felt like we were living in London while we stayed there rather than just coming and going from a hotel. The neighborhood is wonderful. Multiple pubs, an off license at the end of the road where we became friendly with the guy who worked there, a beautiful church, and people living, working, jogging the morning, and we were a part of that life for a short while. There is a canal with boats and ducks that you can walk or jog along.
The Angel High street is also a quick walk - there is a ton of shopping, restaurants, pubs, Starbucks; Sainsbury, Boots and M&S.
Two bedrooms and bathroom one are on the second floor, the master bedroom with bathroom two are on the third floor. The stairs are steep and winding so the only thing I would say is be aware of the stairs if you or someone in your group has mobility issues.
This is a fantastic place to stay in London if you want a comfortable home base and like the idea of living like a Londoner for a short time.