I am retired in HK but my case is a little bit different so I have to explain a little bit more in detail.
In 2001 the company I was working for was a huge Swiss pesticide company which asked me to move to HK to work in their regional office. At that time I was 57. In the course of 2002/03, the SARS epidemic occured and the company opended a new regional office in Singapore I had to move with them. In 2005 I got retirment and I moved back to HK since I met a HK lady working in our regional office whereby her daughter got SARS and nobody took care on her problem and had to stay out of the office for 3 weeks. So I tried to console her alittle bit and step by step a kind of relationship developed. Since I am living separately from my family since more than 20 years I decided to move back to HK and asked for a permant residence which was of course not approved since I did not work for more than 7 years in HK and I did not invest several million HKD.Consequently I was living on a tourist visa and had to go out all 3 months and to enter again the next day. This procedure I made for several years. After several years I asked again the Immigration Department for getting a residence permission but again without any success. Only after I wrote a letter to the office of Donald Tsang who forwarded my letter to the Immigration Department they have granted a 6-month visa without to leave HK.
But from this time the problems started seriously. Each time I came back from travelling, the airport immigration checking my passport for about 5 to up to 15 minutes, asking me question over questions I feel treated like a criminal. People behind me waiting in the queue are getting nervous and look at me angrily. If I ask the immigration officer a question whether I can give some explanations, they do not answer, calling other colleagues, discussing my passport, with other words, the entering into HK is now a pain I never expected. As long as I had a work permission the officers were really polite and nice and in 1 - 2 minutes the passport control was over, but since I do not work anymore the situation is just the other way around. Last week I had to apply for a new 6-month visa and I asked the officer whether there would be the possibility to get access to the e-channel but the answer was short "No, I am not eligible"
In summary I am sure that in HK one cannot get a so called retirement visa. If you did not work for 7 years without interruption or if you are not investing several Million HKD in Hong Kong you have no chance to get a permanent residence. Only money counts nothing else and one can find hardly a certain kind of social behaviour. I have a good pension, I have no criminal record I cost the HK government not one penny, I support a local person which is really not rich, but this is without any interest for the Government. Money is everything.
Although in case I would have a permanent residence I would move out from HK at a certain age since there are not much retirement estates you can live a quiet and a relative comfortable life as it is the case in e.g. Thailand. There is an estate for retired poeple in Wanchai but you have to invest 3 Million HKD and only local people have the right to apply for a flat.
Since I was working long time in Switzerland I had to take a health insurance in Switzerland which is quite expensive but if you are over 70, the health insurance companies offering their products here, are similar expensive and cost over USD 1000.-