What documents do I need for a border run to Mae Sai, and will I need to show cash or a flight ticket?

When traveling to the Mae Sai border for a border run, it's generally reported that you do not need extensive documentation such as an onward flight or bank statement. Immigration will check your passport but primarily focuses on your ability to re-enter Thailand. Also, you will need to pay a fee of either $10 or 500 THB for a day pass to Myanmar. Overall, the Mae Sai border crossing remains easy and straightforward.