The most well-known means of getting around in the main towns would be on the tuk tuk.
If you intend to go to dusty places and have at least four people, you might want to hire a jeep or a car. Otherwise a tuk tuk for small distances would be fine.
Buses are divided into local as well as tour categories. Some tour buses come with toilets but that could turn out to be a blessing or a torture!
