We had 5 great days at Klaus' apartment - the ideal place for a short trip to Prague! Everything was clean, all the essentials are there and it's only a 20min walk to Prague city center (place of the republic). Several stores and a small shopping center are within walking distance.
Although we were only 2 we imagine for 4 it might get a bit cozy.
Communication with Klaus was perfect, we got quick responses via text throughout our stay.