Doing a legitimate business in Thailand is pretty straight forward without any hidden costs. If you are pumping in a substantial sum then the Board Of Investments (BOI) can help you get started. You would also need to get a good business lawyer and an accountant from a reputable firm. Also no harm asking your local chamber of commerce, Singapore has one in Bangkok, for advice.
If starting small business i.e retail shop, restaurant etc. also no hassles. It's only when you want to do a business that involves girls and alcohol then things get a bit problematic. Many under table dealings with the police i.e. the local mafia and various government departments in order for your business to operate.
Thailand like everywhere has it's fair share of dodgy characters and scams. Becareful who you deal with especially those you meet on-line. If you need to keep on putting in money to grease the palms of officials and police then something is not right. This applies for any business big or small, legal or illegal.
