Non o-a multi entry needs insurance for the length of your stay but with a well planned border run you can get 2 years out of it (buying 1 year insurance each time) and doesn't require you to keep
*****
0 in a Thai bank account. O visa doesn't require the insurance but means you have to have between
*****
0 and
*****
0 tied up in an account unless you're doing it through monthly payments
it has been up to 7 days but now a lot less info is required to check so in theory it should be a much quicker turnaround. There'll probably be some hiccups today as it's just launched but should ease up over next few days
If you know you're coming for that long just apply for a tourist visa beforehand. It costs the same as getting the exstension and you don't have to spend a day at immigration. It's all e-visa now so you dont even need to send your passport away
from May 1st testing and quarantine restrictions dropped if you are vaccinated. You'll just need a Thai pass for each entry, which is just uploading proof of vaccination