Tuk-tuks are plentiful in Patong and Phuket Town but travel to many areas in the north or south part of the island may require you to negotiate a round trip rate because finding a tuk-tuk for the return trip may be difficult.
It is generally not difficult to negotiate a rate with a tuk-tuk driver that has him sleeping in the parking lot while you walk around the national park, dine at a seafood restaurant, or watch the sunset at Cape Promthep. Start at 100 to 120 Baht per hour depending on the distance to be traveled and be prepared to pay 150 Baht per hour.
Many tuk-tuk drivers like to double as travel agents - Don’t do it! They will normally only take you to a place that will pay them an additional commission over and above what they overcharge you for the ride in the first place.
The rate paid is by the distance traveled not by the number of passengers. If the driver wants to charge you by the number of people, wave him on and catch another.
The polite way to stop a songthaew or tuk-tuk on the street is to hold your arm out in front of you, palm down and make a up and down motion.