Nice Flat and localisation. Flat is for 17 and really optimized for it, but I would recommand to be less than 14 to be confortable.
Extra cost of 20€ per person/night, but no refund if one person is not coming anymore, even if notified few days before.
Check in and out are really well organized, the person in charge is very friendy and helping and the flat is clean and well furnished (towels etc...).
I recommend it.