Sawbones, I know you asked about "Minimum", but may I suggest you get everything you can. It doesn't cost extra to take the extra tests, at least in Ohio, but if you leave one off.. (as I did) and then go back because you need it at another job, you have to do everything again.
Having the extra endorsements can mean the difference in job offers, if you're in between expedite jobs, or afterwards.
I currently have CDL B with airbrakes, plus X endorsement (Hazmat and Tanker). When I was in between expedite Owner Operators, I was in demand around here.. (Ohio)... I had my choice of Farm Supply co's, Propane, Fuel delivery, etc... (I ended up hauling Anhydrous Ammonia for Farm Supply)..
Anything that enhances your employability is a plus.... and, with the new Hazmat regs, background checks, etc... many drivers are dropping the Hazmat... no way will I drop mine... that's one more advantage...
As they say, just my 2.. !!
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