The foreign exchange rate (how much the monetary unit of your country compares to the baht) will be a major issue for you if you live in Thailand for any length of time. This rate fluctuates, sometimes on a daily basis, and is very sensitive to the political atmosphere in both countries.
Obviously, multiple trips to your home country can be prohibitively expensive so it is advisable to set up accounts in your home country before you actually move. You should choose a financial institution that allows you to withdraw funds from your bank accounts as well as your retirement accounts and get those funds to you in Thailand. To help keep your banking experience smooth and uneventful, it is advisable to visit all of the banks you will continue to use after you move and familiarize them with your needs before your actual move and get them to help you set up access to the different accounts you will need in the most efficient manner.