This is a great, professional day-trip tour of Budapest.
We were staying in Vienna and looking for a guided tour of Budapest, rather than going there on our own. Budapest is only a 2 hour drive from Vienna. Even though Hungary and Austria are both in the Schengen Area, Austria randomly checks passports at the border, so thats why you need your passport.
Peter, who is one of the owners of White Alligator, was both driver and guide on our tour. He grew up in Budapest but lives in Vienna, so he knows the City really well. He showed up at our hotel on time, conducted the tour in a friendly but organized way, and brought us back to our hotel on time. The group is small as the van only holds maybe 8. There were 6 on our tour. The only minor issue for us was a little too much free time in mid-afternoon. We had lunch, so it was fine, but we would have preferred a 'continuous' tour.
Glad to see that White Alligator is now getting credit for the tour. When we searched for this day trip it was advertised as a Viator tour, which is a big international tour operator owned by TripAdvisor. We learned later that White Alligator actually operated the tour - which was a good thing. Don't worry if the concierge in your hotel hasn't heard of them. In Vienna it seems the concierges must have an 'arrangement' with particular tour operators, and won't refer anyone else. Haven't had that issue in other cities.