@Jeremy *********
which visa did you enter Thailand with, and do you want to live in Cambodia or Laos for a while? If you entered with a 60-days single entry tourist visa, the 60-days stay permit you received upon entering Thailand will expire, once you exit Thailand. However you could get a 30-days extension on top of the 60 days, on Immigration for 1900.- THB. You can apply for another single entry 60-days tourist visa at the Thai embassies in the neighbouring countries. However I heard that for the Thai embassy Vientiane, you need to wait almost 4 weeks for an appointment. The consulates Savannakhet and Penang offer walk-in service and application to a SETV. In Vietnam the application is super difficult and very strict. In Cambodia it is relaxed but here, too, you need an appointment