How often is at the discretion of the Immigration officer you are dealing with on the day you enter.

If in thier opinion you are not a genuine tourist and using repeated visa exemption to live in Thailand then you can be refused entry..

Once should be OK.

After that its a gamble until they stop you.

@Roberto *****

I don't believe that's the case..

You should be able to leave to a neighboring country for a 2 or 3 nights and just re-enter Thailand for another 60 days..

The only thing I would say is don't expect to just keep doing that several times consecutively as at some point in the future the Thailand immigration may question you about being a genuine tourist and could refuse entry if they believe you are trying to live in Thailand on just tourist excemption entries.

@Roberto *****

I have Australian passport and got free visa entry from memory so I expect US passport is the same..

Plenty of budget hotels around the $20 to $40 US price in Georgetown..

Check out Agoda hotel booking website or App

Malaysia, Penang or Langkawi

Tell your friend to fly into Cambodia and get his wife and son to meet him there for a visit for a few days.

His Thai wife should be able to easily enter Cambodia and he should have no problem either..

The only other option would be contact a Thailand lawyer expert in immigration law and try to obtain a visa though them..

Thier country and thier rules..

If you don't like it or don't want to comply then you are free to leave at anytime

Just extend, far easier.

But first time border run you would be extremely unlikely to have problems

NO, Deferred indefinitely at this stage so check again at end of April

It's very difficult to say.

But it's far less likely Thailand immigration will ask about onwards travel but not sure on the airline...

I have flown 1 way in the past without any problems..

Just on another note regarding your travel..

Make sure you have a visa for Vietnam BEFORE you travel as there is NO visa on arrival for Australian passport into Vietnam.

You must have a visa before you either fly or attempt to enter by land.

And be aware buying last minute flights back to Australia can be quite expensive as well if you are planning to do that..

Australian passport you get free 60 days visa exemption entry to Thailand.

Nothing required, just show up at immigration with your passport.