Getting around Cambodia is relatively easy. There are buses that operate between cities and towns and private taxis that do the same thing.
Within a city or town, you will always find a tuk-tuk available – there is even an Uber-type app for tuk-tuks now. You can also choose to hop on a “scooter taxi” which is simply sitting pillion on the back of a scooter.
Scooter taxis and mopeds are easily hired and are inexpensive. it should cost about US$1 for a short ride on the back of a scooter and tuk-tuks should not generally charge you much more than US$5 for any trip unless you are heading out of town. US$2-3 is a standard fare for a tuk-tuk ride.
It is always a good idea to negotiate the fare up front once you have told the driver where you want to go to avoid an argument later. Remember bargaining with a driver is as acceptable as bargaining with a store owner in a market. Expect to pay a little more if you are travelling late at night.