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BUT if you are uncomfortable with it, wax the car. I say wax because it is more forgiving. If you forget to wipe off the wax completely, you can just remove it when you notice it and no harm no foul. With wax you would have to do it more regularly than if you applied a ceramic coating though. With ceramic, you only need to apply once every year, maybe 2 years if you are good about topping it off with product that extends the life of a ceramic.
I'd like to assume garage storage will not happen always. If parked outside, how does DIY ceramic coating yearly vs waxing 4, 6 times per year compare?