My adult son and I booked directly via HongKongFreeTours.com. We were lucky enough to have Micheal (founder of company) take our group of approx 12 people. So informative. This was based on Micheal's family background, how they came to be in Hong Kong, what the future may hold; fascinating for a visitor from NZ. We were able to ask many questions.
Great mix of commentary on current events, local landmark buildings and hints of what to do while visiting Hong Kong. You receive a copy of their map which is worth HKGD100 on its own, lots of points of interest on the map. We were happy to tip more than recommended as it was the highlight of 3 days in the city.