The place is clean, warm, quiet big with a separate bedroom and a big bathroom. Very central also, maybe even too central (located on Karlova street, which is the busiest street of the old town, connecting Charles Bridge and the Old town square), however it's not too noisy and we had quiet nights.
Communication with Kateřina was easy, you just have to know that you will have to get the key somewhere else (5 minutes away). Very convenient place if you're travelling with a baby!