The service at the Chiang Mai location is acceptable. The car we rented likely didn't undergo a major service at 60,000 kilometers, as the brakes were extremely ineffective and almost caused several accidents. Luckily, there was little traffic on the road! It seems the brake pads weren't replaced. We struggled to drive to Bangkok to return the car, but they didn't even refund one third of the cost! Moreover, the service attitude at the Bangkok airport location is extremely poor! Quite disappointed with such a large rental company. Definitely won't choose Avis next time!