Also, as you mentioned "cheapest" keep in mind the cost of the visa when choosing a destination. For example, for me, a visa to Laos is $42, Vietnam cost me close to $90, Malaysia $0, Bali $0 (although some destinations in Indo do charge depending on where you land).
Green bus is easy and comfortable. You can buy tickets online and pay for them at 7-11. I typically take the 8 am bus there and the 2:30 bus back. There's a 15 baht song theaw that takes you from the Mae Sai bus station to the border...easy easy.
Used to be only multi-entry but it has since changed and you can do a border bounce there to get 30 day exempt entry (limit 2 per year by land crossing).
I have not heard of anyone having to show 20k baht upon entering at that border.
You will need $10 US or 500 baht for the Myanmar immigration officials to stamp you in/out.
Technically the immigration officials at the border can request you have 20K with you when you enter the country again. But I've personally never heard of that happening at the land border from Laos. It has happened to people flying into BKK and DMK though.
Yeah.... noticed I couldn't report from my phone either. I reported to facebook as some of the activity was requesting illegal information but, would have been nice to boot him immediately.