All techs have laptops, except lube tech and he has older PC.
Likely will only purchase laptops for shop in future. PCs take up a lot of the tool box / work bench area. Laptops make test drives easier

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A question for you. You said your techs brought in their own computers. Do they connect to your in-house system? If so, how does your dealer handle security? Do you have a BYOD (Bring Your Own Device) policy? If you have a written policy I would like to see / read it. This issue has come up at our dealership in the past and I have always kept BYOD's outside of firewall - no exception. One tech has his own laptop and company laptop on his tool box. He connects his to our customer wireless connection and streams music. Since that is a separate "slice" of the bandwidth I don't police that.