5-6%? You can just buy a US treasury bond for 5% yield risk free. Investing in Thai properties put you at a serious disadvantage. The Chinese loves buying condo here because they are laundering money out of China. They just leave the condos empty. Thai properties are uninvestable.
Why on earth would you buy a condo to rent it out here? A Thai person would buy it 30% less than you and be able to rent it out cheaper than you. The moment you sign on the dotted line, your property will depreciate like a new car driving off the lot.