I had my 05 Prius in to the dealer for an oil change and rotation. The car has a little over 16,000 miles. Living here in Florida, the AC gets a huge workout. I opted to have the evaporator coil cleaned, and although I don't have an odor problem, I was amazed at how nice the conditioned air smells now. They said the coil had some mildew in it and the cabin filter was fine. I also had the induction system cleaned which tends to build up carbon deposits. This involves the cleaning of the fuel combustion system and throttle plate. Again, I was surprised when I drove away from the dealer how much more pep and power the car displayed upon acceleration. The entire service was $148.30
You could have done the same work numerous times with a $2 can of Lysol and a $2 can of carburetor cleaner and a $3 bottle of injector cleaner. It's as simple as setting the blower to fresh air at max speed and spraying the Lysol into the blower intake in the windshield cowl. For greater effect, you could replace the cabin filter. I keep a can of Lysol under the kitchen sink for regular use during the height of mold season. As for the fuel injection cleaning, they simply spray some carb cleaner on the throttle plate with the engine running to remove some of the very small amount of dirt that builds up on it. In this day and age, it does very little to help the engine. The fuel injector cleaner is dumped into the gas tank.