What is the best visa option for a Canadian looking to start in Thailand and transition to a retirement visa?

Canadian seeking visa help/clarity for best visa option (stv tourist etc etc) .

I am reading too much and very confused and appreciate constructive help.

-Currently in Canada and single, no connections to Thailand currently.

- seeking longest visa available as a tourist to start

- visa that allows me to upgrade to a retirement visa

- will make the deposit at a Thai bank for min 60 days for the retirement visa requirement

- would like multi entry. Expect to return to Canada for holidays or emergency for family.

- this is my first trip to Thailand, but no concern to sell everything and go. Trying to early retire less expensive than Canada.

-want to be able to travel around se asia ( after covid of course ) so multi entry is important for later.

- concerned a tourist visa won’t give me much time to arrange a retirement visa In country. (Need 60 days deposit plus 15 days quarantine is 75 days already. Will need to find a lease condo to get a bank account etc. ) therefore I need at min. 90 days preferably 120 + for all this.

So what visa has restrictions of not being upgradable to retirement, can last long enough to arrange this , in country application as we do t know what will happen with lockdowns further etc.

If you have gone through this or have real advise , open to DM if you have time.