Can highly recommend it for a bigger group. We spent 3 nights there with 11 and it was plenty of space. It's a huge apartment right in the center of Lisboa, location is perfect to experience the neighborhood and entire Lisboa.
Communication was always very quick and professional. We got services offered before we arrived from pick up at the airport to a boat ride (catamaran) before we came for absolutely reasonable prices. By the way, the latter is something I would recommend too. A nice 2 hours ride with a skipper including opera bar and BBQ.
I would probably not go there with 17 pax unless you don't mind sleeping with 4 in one room. But of course that is possible too. For us 11 we had plenty of space and we enjoyed it a lot.
Three bathrooms and two showers as well, well equipped kitchen etc.
If you're bigger group and want to have a good time in Lisboa - go there