It's pretty standard in many countries.

@Ben ********

Yeah, a guitar amp or microwave will most likely be made only for the electrical grid of the country where it was sold. But phones, iPads, laptops, *rechargeable* razors are usually compatible around the globe. A plug-in/corded razor, mixers, etc. will not work even with a voltage converter. Anything with a motor requires that the hertz match, too. I found out the hard way when I paid for a converter and my clippers still didn't work. The noise they gave off because the hertz was misatched sounded like armageddon.

@Jamie ********

Depends on the ticketing and airlines. If you use an online booking site that breaks up your flight legs into separate tickets, you well could shafted on the first leg of LAS to LAX/SFO/...or wherever. Southwest, Frontier, Spirit all charge extra for each check-in bag. The transpacific leg will usually allow two free checked bags of 22-25kg. But then your final leg to Bangkok could be on cheapie carrier again, like VietJet or AirAsia. Try to book all the way through on a single ticket unless the airfares are dramatically different.

Last month I flew from BKK to LAS and it was on ANA which codeshares with American. Two free checked bags at 25kg each all the way through.

@Pertti ************

This.

@Tony ********

A person new to Thailand can get a one-time exemption to import personal effects duty free.

OP: Others are correct that it's probably better to buy in TH what you find you need. But you can look up the rules to comply with the exemption and send (or bring) some things that way without paying duties. There's a time limit and a value limit, but it's worth looking into now as it's a one-time thing.

@Ben ********

Electronics like cellphones, laptops, etc. will be okay. But plug-in electric razors, monitors, etc. most likely won't work. Need to check the listed voltage on whatever device one considers bringing.

@Sri **

You're overpaying.

@Ralph ******

Best answer.

OP: I entered Thailand twice this past summer. Both times from Japan. The first time I flew on Zip Air and they were anal, checking my ongoing ticket and even my hotel reservation.😑 The most recent time I flew in on JAL. I took a chance not yet having an ongoing ticket, but got away with it. Don't know if my anecdotes help or not.

Maybe have this site loaded on your phone when you check in and if you get any grief, step aside and quickly book something through here. Then return to the counter with a Cheshire cat grin.

@John *****

Interest rates cuts are coming in the US. The dollar already peaked for the foreseeable future, all other things being equal. If the Thai economy abslutely crashes or something even more dramatic than the two wars already underway happens, all bets are off, though.

@Angelo **********

Okay, well at this stage in his life, OP needs to first visit and stay for a while. If he falls in love with Thailand, he'll need to be mindful of the long term requirements for living in there, whichever path he chooses/can qualify for. So I hope he's reading all these responses and is getting a better idea of his options and decisions to consider.