Honestly, I don't know why anyone ever decides to travel in one of these things but it does seem to be a way that a lot of tourist want to get around. I don't like it because it is noisy, dirty, hot, and slow.
Another reason to dislike it is because this profession seems to attract the worst and most unscrupulous members of society as drivers.
These things are powered by LP gas and you can tell this is the case as soon as it gets moving. I don't think LP gas stinks per se, but you do become quite aware of the fumes you are inhaling as you putter on down the road at a volume that makes conversation almost impossible without shouting. I almost never use this method of transportation but whenever someone is visiting me from abroad they are really persistent in demanding that we do it.
The internet is awash with stories of people being completely ripped off by these guys and due to a general lack of regulation, a lack of meters, and a lack of sense on the part of the passenger this sort of thing continues.
here are some tips
Always talk price before you even sit down
There is no meter, and if you just jump in and tell the guy where you are going and don't talk about the cost before you leave, you almost certainly will be ripped off. While this scam is mostly geared towards foreigners there are plenty of stories of Thai nationals being ripped off as wel. In the digital age when anything can go viral these days sometimes people will gain some traction about the ripoffs and the police always promise to do an investigation and to introduce some safeguards for passengers but guess what!? this never actually results in anything changing. They just deflect long enough for people to forget about it.
So always make sure you have a price established before you ever depart and it is a good idea to pay them before you ever depart, so that he can't play a food and demand more money than originally agreed upon once you get where you are going.
Never agree to "one stop"
I have been told reasonable prices for a trip on Tuk Tuk's in the past, then sat down with my friend to have the guy turn around and say "one stop" or "we stop one place on the way" or something along those lines. When this happens, get OUT OF THE TUK TUK right away. This "one stop" is a tourist trap where you will be expected to go inside and look around, it will be a tailor or a massage parlor or some other ripoff establishment. Sometimes the driver will refuse to carry on until you go inside. This has happened to me before and I just didn't pay the guy and hailed a taxi. He became violent towards me at that point but I was quick enough to avoid a beating I guess.
These criminals all stick together and you will find yourself swarmed by a group of them really quickly if you don't stay on your toes.
It's unfortunate, but check your sympathy at the door
Often these guys will have some sob story and lately it has been how fuel prices are so high but there is a place that will give him free gasoline vouchers if he is able to bring people by to "have a look"... just 5 minute, 5 minute only. Something like that. They will have pictures of their family on the dash and a crocodile tear moment about food scarcity and what not. It's all bullshit. These people are criminals and they are actually very good con men.
As much as it might pain you, unfortunately you have to presume that they are all liars even though some of them might actually be telling the truth. The fact of the matter is that this song and dance started in the past decade and worked for a couple of them and now a majority of them use this scam. It reminds me of the story that happens at US gas stations where a man is out of fuel and needs to get his family home so could you spare a few dollars for gasoline? Unfortunately this is almost always a lie and the guy in question doesn't even have a car.
I don't know what it is about the tuk tuk industry but it seems to attract con-artistry.
At the end of it all I would say the best way to avoid being ripped off by a Tuk Tuk driver is to just not use a Tuk Tuk. With the apps we have for taxis these days using one of these unregulated un-metered transports is completely unnecessary. But if you must go on one in order to fill up your Insta or whatever the hell it is that you are after, just keep your guard up.
I can almost guarantee that after you arrive at your destination sweaty, partially deaf, covered and dirt and smelling like fuel, that you probably wont want to use one ever again anyway.