Twin Cities School automotive training is individualized and practical. You’ll learn at your own pace to develop and master the skills needed to qualify as a JL Griffis certified auto detailer. The length of training to become certified detailer is 12 weeks. Studies have shown that people learn best through a combination of direct instruction and active learning which our school offers in a hands-on setting. If you are serious about an automotive career, Twin Cities School is here to provide the training you need to succeed in the high-demand and lucrative automotive industry.