We had a great 4 night stay at Harms place. The location was perfect for getting around Amsterdam on foot and we found the apartment very easily from the bus from the airport due to Harms directions.
There are good tips for your visit at the apartment and Harm lives across he hall of you need him but thankfully we didn't have to bother him.
The bathroom is very small but very functional, the kitchen is perfect for preparing a small meal but wine glasses would have been welcome.
Communication was always very prompt via messages through Airbnb and Harm kindly let us keep the apartment until our evening departure.
We would definitely consider staying here again if we find ourselves in Amsterdam in the future.