Officials on Spain’s Balearic Islands want to ban non-residents from buying property as soaring prices in Mallorca, Menorca and Ibiza drive local people out and create “ghost villages” of empty homes.
MSN

Have heard these stories on the news in Germany last year, would be very hard to change though and the islands are already in foreign hands. In reality it still wouldn't make rents affordable as people would still retire there and more money to be made with tourists. Technically somebody could just become a resident, then buy the mansion and move back to where they came from.

Guardian running this
https://www.theguardian.com/world/20...droidApp_Other

The easiest thing to do is to increase the taxes that are payable on sale or renting. Many foreigners are buying properties because they are seen as providing good returns. By increasing taxes it will put people off buying as investments and encourage people to buy as homes. Most Spanish don't speculate on property in the way that people from Northern countries do.

But isn't that another problem and you also need private landlords, otherwise there would be even fewer rentals. Even if people buy as homes and many do (for retirement, leisure etc.) locals still can't afford to buy on an average salary. Although not due to tourism, Jersey has similar problems and they never came up with a solution. The 5 year residency rule still doesn't help those who can't afford homes.

Maybe another solution would be to reward people who rent out their homes below market value to locals. The government then pay these people the balance as a reward. At least this would bring people together rather than creating more divide.

Doubt that would work as the owner could then conspire with the local tenant to inflate the rent and split it (I thought Spain was trying to stop back handers).
If someone like me can think of a simple dodge like that you can bet most others will.

Why not just rent cap everyone and be done with it?

That certainly wouldn't work and how would you split it or what benefit would they have? In an employment contract I also get the correct bonus if it's regulated. The idea is to have more rentals available, but a rent cap actually fuels more poverty and even here I could sub-let. It's no different with littering and fines don't stop it. If you reward people for bringing their litter (bottle deposit scheme etc.) they are less likely to dump it in the countryside.

In Thailand, only Thai can own a property / business.

There’s a well used loophole for that rule as well, marry a Thai citizen.
Unfortunately whenever a rule is introduced regarding money, it will be exploited.

True and we are also in the EU, meaning these islands have benefited from the funding over the years.