We highly recommend Marketa's apartment!
For travelers with young children, this is the perfect location. It is located between Stromovka and Letna Parks (enormous) and there are plenty of large playgrounds with friendly local and international kids there. We would see the city all day, while the kids simply begged to go to the nearby parks.
The apartment has a great shower and really fast internet too. Clocked the internet at 150 mbps (much better than at home!). I would play online games in the evening! It is also worth noting that there is a small elevator for those with trouble going up the stairs.
We had an unusual request to store lots of extra luggage (10 x 23 kg bags!) and we were allowed to use the downstairs cellar storage. Of course, such a request is above what an AirBnB host is required to accommodate, but we were pleasantly surprised to be allowed to store them for the duration of our stay!
Another benefit is that the housekeeper lives right across the hall! Of course one should not burden neighbors, but it is quite helpful to have a knowledgeable, and helpful site manager right next door!
Thank you Marketa! See you next summer!
-The Moodys