There is actually no fee to open a bank account, but most banks will require a initial deposit of 500 baht to open you a account. If they are asking a fee, or are trying to sell you insurance, walk out and try another branch or another bank.
I have had the same TM30 for the last 6 years now, as I live in our house, your TM30 will be valid, until you change addresses, or returning from a overseas holiday, some offices will require you to lodge another TM30 upon return to Thailand, even if you are returning to the same address.
You also might require a completed TM47 form in blue ink, a lot of offices ask for it now. Plus your passport, a up to date TM 30 and you should be fine.