Which countries/islands allows people to buy real estate/land using alt coins?
I don't know about any established crypto-oriented platforms where you can do this right now but there are some ICO projects
currently with plans to offer real estate investment. You can look up Brickblock, Wealth Migrate and Alt Estate. They are upcoming cryptos centred around real estate business
If you want to read more about Alt Estate or Wealth Migrate check these reviews:
Alt.Estate:
https://steemit.com/ico/@rdmtv/alt-estate-project-and-market-description
https://steemit.com/ico/@rdmtv/alt-estate-meet-the-team
https://steemit.com/ico/@rdmtv/alt-estate-tokens-policy-and-pros-and-cons
Wealth Migrate:
https://steemit.com/ico/@annahare/wealthmigrate-project-review
so just follow the progress of the project project to get more information