We had had Avo as a tour guide just two days before on a different tour, so we knew we were going to have a good guide. There were just the three of us in the group, so it was truly a private tour experience. If you are into Dan Brown style of mysteries, this is definitely worth your time. Avo has done a lot of personal research on many of mysteries hidden in plain sight in Brussels, but it was really interesting to have things pointed out to us that we hadn't noticed, like the Camino de Santiago. Definitely worth doing!