Best I can figure in California is if the trailer is rated over 10k you need a class A. Even if the trailer is empty.
Vermont says that, then later in the rules they say the scale weight of truck + manufacturer's maximum rating of trailer added are under 26000 it does not apply.
Vermont legislature wants everyone to live in an apartment & drive a Prius. They prefer you not be employed, that messes up their utopia. The only acceptable pastimes here are marijuana, or skiing. They will throw obstacles in the path of anyone who deviates. CDL should not be an obstacle except for the DMV in your state. As the law is written, you have to understand the braking system of your vehicle. Then you get a manual. The written test penalizes people who think. They want you to recite the manual word for word. It is filled with questions deemed incorrect when your answer deviates in any detail from the manual's text.
Then the medical card you were told you didn't need is required. "Sorry, it doesn't matter what we told you 30 days ago. The law is changing in July, this is April, we're enforcing it early."
Next round, pre trip inspection: "I'm failing you. You didn't inspect your trailer's headboard, or landing gear. You failed to inspect the truck's windshield or mirrors." I argued the trailer doesn't have a headboard, or landing gear. If there were a problem with windshield or mirrors, I'd have noted them this morning before driving here. He replied: "You need to mention these things."
Next round, they had no record of me having an appointment. Go away, reschedule.
Next trip I was Bill Murray in the movie Groundhog Day! I spent two hours on pre trip inspection. I had him begging for mercy! He had heard more commentary on the condition of every frame bolt, level of fill in every cavity. I bored the most boring man living to the edge of death by boredom.
Eventually he called off the pre trip inspection before I was finished. He elected to move to the dock backing phase. The state highway trucks were parked in the way. He asked if it would be necessary to move them. I was catching on that all questions are trick questions. I fought my nature to say: "Yes they are in my way."
Passing the dock backing test, I believe he was reluctant to let me do the road test.
In total, my CDL license took 5 trips. Four of them by VT law, I had to be accompanied by a VT licensed CDL driver, and appear at the test facility in a heavy truck with trailer.