Out of all the popular cities in Thailand, Bangkok is the cheapest city to rent a car in at just C$ 20/day. Renting a car in Bangkok is 25% cheaper than renting one in Krabi where the per day rate is around C$ 25. Other fairly inexpensive cities in Thailand to get a rental car in are: Chiang Mai (C$ 21/day), Phuket City (C$ 21/day), and Koh Samui (C$ 25/day). While these cities typically have cheaper prices than the rest of the country, travelers looking to rent a car in Bangkok should expect to spend around C$ 20/day on their transportation. The most popular city to rent a car in Thailand is Bangkok.