First off OP you wont be under 10k with that rig, depending on the year and style of truck you will be sticker weighted at 20 to 23k, which means you do not need a cdl but since you are doing it for hire you will have to register your truck commercially, get a ca dot number or usdot number if you cross state lines, you will also have to have a dot med card and commercial insurance. You also have to have your dot and mc numbers posted on the sides of your truck in block letters atleast 2" tall. You will be required to run a log book when you are loaded even without a cdl, if you get a cdl you have to run logs loaded and unloaded. You say a company will put you on their insurance, you have to be careful because when companies say they will put you on their policy they usually mean on their cargo policy, the 100k the feds require, you still have to put the 1 million dollars insurance on your truck, it is smart to get both insurances throught the same under writer because if you dont and you have a wreck the 2 under writers will fight each other in court and you will be caught in the middle.
Im not sure who told you that it is illegal to go through the scales in a pickup but they dont have a clue what they are talking about. If you haul commercially, which is for hire, YOU ARE REQUIRED BY LAW TO STOP AT SCALES. We have a 2500 and you can see our loads in my hauls thread and we are required by law to stop at scales. Asking the dmv will get you fined real quick, none of them will give you the same answer, you need to buy a current fmcsa handbook and study it, and be able to back, in writing, the laws at the scales.
Some states like Nebraska for example, and there are others that do this to, ANY VEHICLE PULLING A TRAILER MUST STOP AT THE SCALES. Every state is different, we have been to 36 states in the past year and 99.9% of them will make you stop at the scales, even California, we haul trailer to the port in los Angeles.
Goose is right on the gvwr, you have to keep your sticker weight under 26k and you also have to be careful to keep your actual weight under 26k also.
By not going cdl, you get to skip running a log book empty and since they changed the laws you dont have to pay ifta now. You also get to dodge some other fees and hassles but im not going to go into those since you wont be cdl weight anyway.