I have been looking at this post for 2 days now, rabbit. I don’t know the laws in Mi, but in PA if you are under 10000GVW and are going to run intrastate only, all you need is a state PUC#. Or an ICC# (Interstate Commerce Commission) To run interstate you only need a MC# (Motor Carrier), over 10000GVW or ICC (Interstate Commerce Commission), any GVW, not an MCC# (Maintenance Control Center).
Is this what you are asking? There are so many letters now a days, I don’t think anyone knows what they stand for. I do know! If you want to run as an individual you do need to get registered. You will need an ICC# You will not need a US DOT# under 10000GVW, unless you are carrying has-mat.
If you run under another person, or company’s authority you don’t need anything. You will also be required to carry a certain amount of insurance, depending on the way you register.
I don't know what Mi requires you to have!