We received a very warm welcome from the start as Jiri and his wife(?) were waiting for us at the door. From taking our luggage, showing the beautiful, modern and very clean apartment, to explaining all the little places-to-be in Prague while drawing it out on a map. They were very enthousiastically helpful and also helped us booking a taxi for our return several days after. The location is great as it's just a 2 minutes walk ( 1 street away) from the Astronomical clock in the Old Town square, from where you can go pretty much everywhere.
Highly recommended!