A painful experience to warn future renters: avoid renting from National at all costs. Here's my story. The rental process went smoothly, and everything was fine during the use. However, I probably hit something sharp, which caused a cut on the tire sidewall, rendering it unusable. Since I didn't purchase full insurance, I had to cover the tire loss myself, which cost me 2390 THB. Though expensive, I accepted it. The problem arose when I returned the car. 1. During the car inspection, the inspector actually got on the ground to check underneath the car (a first for me after many rentals), and pointed out scratches on the underside of the front bumper, claiming I caused them. When I picked up the car, I didn't get on the ground to inspect it either, so even though I had doubts, I couldn't argue effectively due to the language barrier and accepted their claims, thinking a paint job wouldn't cost much. 2. Then it came to the charges. Since I didn't have full insurance, there's a deductible. I was charged 2390 THB for the tire plus the deductible of 8560 THB, totaling 10950 THB. After communicating with the rental company, they said it was a pre-payment and any remaining balance would be refunded after the actual damage costs were finalized, to which I agreed. 3. Upon returning home, a few days later, the final damage report came out. Besides the tire, they pointed out three more damages that weren't mentioned initially, and put all of them on me. In the end, I didn't get any refund at all.