moldy smell in 2018 camry SE

Did you get a car fax ? Was it in a flood ?

I try to remember to turn off the AC a few minutes before I shut off the engine. This way the cooling coils are dry which reduces the chances of developing mold or mildew.

Try replacing cab filter

I was told by my local dealer, it is due to a change in the freon they are using in the 2018 cars that causes more condensation, then molds and smells within the vents. I was told the only remedy was to turn ac off prior to destination (good luck remembering that) and also spraying lysol once a week in the exterior air vent by front windshield while the defrost is running in the car. Personally I find it absurd to do such things on a newer car and am not happy at all. We have 3 Toyotas and this will most likely cause me to change over to Honda after his experience.

Honda is going to use the same refrigerant soon so if they don’t have a problem now they will have unless they modify how the system cycles and drains off the moisture.

Are you pulling in outside air usually? I noticed that ever since keeping the recirculating air option on, the musty smell decreased considerably.