I have one word : PERFECT!
The apartment was absolutely great (and so clean!) with plenty of space (we were 5 people)! It is actually bigger than what we were expecting!
The location is really good too, very central, just near the IP Pavlova station where we can take the Tram 22 which goes everywhere.
The reception works 24/24 and Sofia, the young woman at the desk, was a pearl! She agreed on printing our boarding passes and she kept our luggages for the day.
In short, we had a lovely time in Prague with this apartment!
Thank you so much!!