We had a great time in Berlin. It was very hot outside but rather cool inside. There was enough space for us; with my mother of 80 years and our children of 19, 17 and 14 years. There was quite a lot information about Berlin and Ralph was very helpful with everthing. We could park our car just outside for free - all we needed was a Umwelt-ticket.
Just one bathroom with the toilet inside is not always practical with 6 people, but it isn't easy to change that.