I have just joined the forum (19 March 2018). I live in the UK and collect Chinese stamps from Imperial to the PRC, but not Hong Kong (though I have lived there) or Macua or Taiwan (that is, apart from when it was province of China). I have collected Chinese stamps off and on for years (about 60+) but never really put them properly in albums. So now I am retired I have the time and inclination. For this I am going to need some help with identification of some stamps. I use Chan (2010 edition), Scott (volume 2A 2018) and being a Brit, Stanley Gibbons of course (11th edition 2015).
I am also looking forward to offering and buying/exchanging stamps through the Society.
My main regret it that when I lived in Hong Kong (in the early 1980s) I never bought a single stamp - can you believe it? I bet the cultural revolution stamps were rather cheaper then!
Those are Chinese revenue stamps, and hard to find, but there are catalogues out there that will help. You might want to post this in the revenue thread on this forum as many people who collect them are just as passionate about them as others are their favorite areas.