The country you are looking for is Uruguay.
- tax free country: It is a territorial taxation country. You can become tax resident by living 6 months there or by owning real state or other forms of investment in Uruguay (see
Uruguay - Individual - Residence). For the first 10 years of tax residence the IRNR rules apply to you as an individual, which are more beneficial than the normal IRPF rules. Free zone companies with 0% corporate tax exist (although they require hiring Uruguayan citizens), and you won't pay personal income tax on dividends from them. Non free zone companies engaged in software development pay no corporate tax and their dividends are not taxed for individuals, but this type of company must employ people (hire yourself, pay minimum salary, that will make it easy for you to get residency permit anyway). Non free zone companies engaged in trading goods or services where source and destination countries are not Uruguay (for example, e-commerce buying on China to sell on Amazon USA) pay a bit less than 1% tax in total, including corporate and personal tax from dividends.
- country/island with fresh water available: plenty of fresh water
- nice vegetation: plenty of nice vegetation and nature
- calm sea: calm sea to the south, a bit stronger to the north.
- beach: plenty of beach
- min. 10 acres: plenty of acres to buy
- no close neighbors: just avoid Montevideo. It's full of socialists there anyway. Try anywhere to the east of Montevideo that is close the beach and green.
- ideally (not necessarily) a peninsula: the most touristy part of Punta del Este is a peninsula.
Bonus points: residence is easy, mostly you need clean criminal record and proof of foreign passive income or an employment contract (hire some lawyers to help you start your company remotely and sponsor your own visa). If you are a Mercosur citizen, you don't even need employment or income to get a residence permit. Personal and corporate banking is easy once you are resident. After 5 years you can apply for citizenship (or 3 if you marry in Uruguay). Also, no need to submit yearly asset returns nor report any foreign source income.
If you like nature, good food, nice weather, no natural disasters, a very slow pace of life and hate taxes, Uruguay is probably one of the best places to take residency in. The area around Punta del Este is full of expats.
Here's some country-side real estate offers from around Punta del Este:
Venta de Chacras o Campos en Uruguay - infocasas.com.uy
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