I would recommend what Lite Beer said, and enter on a Visa Exempt or even on a 60 day visa, then go and apply for a 1 year retirement extension, and with the two of you being Canadian can get a Income verification letter from the Canadian Embassy, but you will have to show them proof that you have 65,000 Baht or more per month. I usually just show them a copy of my tax return, as they still issue those, that way you don't need to keep 800,000 Baht in a Thai bank. I use the Income Verification method for my retirement extension.