Hi guys, I'm certain there's a similar post on something similar here but after going through more than a dozen I start getting dizzy...

I'm a Polish and British national. Planning to go to Thailand for 6-12 months. I'd like to do a little bit of work on the side as a musician but mostly chill out, hopefully learn some Thai and if possible do some volunteering.

I'm not sure which route will be more sensible: SETV (60 + 30) - I don't fully understand how many times can I get in and out to renew (there's the 2 times per year rule);

METV (90 + 30?) - can I get a SETV after? Doubt I can get the second METV...

Also, as I have two passports, can I maximise by using these (in order not to have too many stamps in one?

Please explain like to an idiot...