Weight is always a hot topic!
Not what you weigh, but what does your vehicle weigh? The magic number is 10,001 pounds. That is when your company vehicle becomes a Commercial Motor Vehicle (CMV). Also any weight vehicle if it is hauling placardable hazardous materials is considered a Commercial Motor Vehicle.
For example, your company pick-up weighs 5,000 pounds. You attached a small trailer to the pick-up that weighs 1,500 pounds. Now you load that trailer with the tools of your trade, say 3,625 pounds. You, my friend, now have a Commercial Motor Vehicle that weighs 10,125 pounds and is subject to all the FMCSA regulations.
These regulations include having a USDOT number on the each side of the truck and being in compliance with vehicle inspection and maintenance rules according to § 396.13 and § 392.7.
Now lets talk about the driver. The driver must be qualified under Part 391 and comply with the hours -of -service regulations. If the driver does not fall in to the short haul exceptions in § 395.1(e), then the driver is regulated by all the log book rules.
Much to consider when you own or manage a business!