First of all, it's hard to trust anyone or any agents. So just research deeply. Sadly my country doesn't allow foreigners to buy land directly. The only way is to take a business license and  Registrar of Joint Stock Companies. This means you have to open a company here, no matter small. Then you can buy property here legally belonging to the company name and you can sell it at any time you want. Since you don't want to buy sell and going to earn from rent, then there wouldn't much issue and you may do it without hassle. It doesn't cost much though.

By the way, just stay away from scammers. Likely scammers would PM you and propose for the business. Just ignore them and ask to discuss them in public. This is a financial decision, so make sure you are going to deal with a trusted person.