Need advice concerning our retirement plan to Dubai

I would be very grateful for any help or advice concerning our plan to retire to Dubai.

We plan to sell up and retire to Dubai in just over a years time. We see no future forces in the UK and want to take advantage of the tax (or lack of it) and enjoy the lifestyle.

We plan on entering Dubai on a retirement Visa, buying a property for 2 to 2.5 million UAE D and then changing to a golden visa.

We need to purchase private health insurance which seems to he a minefield of choices. I was hoping to pay for this with the tax savings we would make. After some research, we won't be using the big names like Cigna, our budget, for both of us is approx 30,000 UAE per annum which means we'll be using a local provider i guess.

I am somewhat confused with the real estate market in Dubai. How does one buy and sell a used property? Buying something that hasn't been built yet seems the only thing I can find online.

Another question is visa/health insurance. I've read you need private health insurance to get cash visa but in order to purchase health insurance you need a visa/UAE ID. How is this negotiated?

Finally, we are not rich but have been to Dubai and didnt find it much more expensive than most major cities. We envisage our livable income to be approx 12,500 UAE per month. This is with no mortgage/rent and after healthcare insurance. Bear in mind we will be retired and will lead a relatively quiet life. Is this a realistic amount of money to live comfortably on in Dubai?

Any help woukd be greatly appreciated.