We really enjoyed our stay at Adam's place! We didn't meet Adam (this apartment is in fact rented by a company), but the self check-in was very easy and the communication with the agency was always fast and helpful throughout the entire stay.
The apartment itself is very nice and can fit you to 4 people, so it's perfect for a small family or a group of friends. The kitchen is well stocked with all the necessary equipment (although it does lack basic groceries such as olive oil, for example, so you'll have to shop before using the kitchen to cook).
The apartment is not very close to the city centre - it's a somewhat easy 30 minute walk to the old town square (you'll have to cross a railway area with an express way of sorts - it doesn't seem to be a dodgy area but it's not nice). That being said, the area where the apartment is located - Zizkov - is very wonderful and perfect to those looking to explore a less touristy part of town.
Check-in and check-out times are rigid (although they suited me fine) so be careful when booking, as you'll need to vacate the place at 10am.
To sum up, I would definitely recommend this apartment (no problems with the boiler or heating as had been mentioned before in other comments)! Thank you very much!