Can you describe your exact situation? If you can provide more details, or a scenario or two, it will be easier to point you towards the optimum solution.

You have a passport which allows for a 30 day visa exemption, let's say from the U.S. or one of the 47 ~ 51 other countries?

And you want to travel to Thailand and stay for more than 30 days? How many days maximum? This is really key to getting to the best solution.

A 30 day Tourist Visa Exemption can now be extended for an additional 15 days inside Thailand, for a fee (1,900 THB?), which would allow for a max. stay of 45 days before you have to exit the country.

I always recommend getting a real Tourist Visa as these always overcome any potential IDB situations (proof of onward air travel), and can be extended inside Thailand.

http://thaiembdc.org/consular-servic...s/category-tr/

If you planning on retiring in Thailand, that will call for a different solution. (Visa, then Extension of Stay based on Retirement).