There is no public bus Patong - Kata. Tuk Tuk cost depends on time of day and your haggling skills. 400 baht would be about the low price, after mid night could be 1,000 baht. Just recently tuk Tuk started a minimum price of 200 baht even to move 100 meters, so my suggested prices might be on the low side. Oh, and the charge increases with more passengers. Driver will argue that uses more gas, and there is a big hill over to Kata ... bla bla bla. I hate Tuk Tuk drivers.