Maybe look into doing more of the hotshotting above the radar as it is proven profitable for you. Just make sure to have good commercial insurance while doing it. Even better for a LLC, that you may already have, to help with taxes and liability.
If I went above the radar wouldn't I have to get a CDL? As it is now, I get paid for doing work at the site and reimbursed for expenses, which works out very well. I can claim I don't get paid for driving, which I believe is where the CDL, log book, etc come into play.
I don't recall my towing CPM being so low - 1/2 the MPG and 8 tires on the road with extreme grades. Flat land would give me 1/3 better MPG. Lake Havasu runs would be 12MPG vs. the 7 MPG, yes 7 MPG, on the 7% grades that go for miles going east of Phoenix. Just fuel alone was 0.38 per mile.
I just checked my spreadsheet, and for 275K miles my total CPM, which includes purchase price, fuel, oil changes and all other truck related costs but not insurance, registration, inspections, etc is $.36/mile. I've learned that if I keep the RPM's right at about 1800 (roughly 68MPH) I can get 18-22MPG on the highway, depending on wind, even if I am hauling stuff in the bed. I've had 3K in the bed on the outbound side for some trips and gotten 18MPG. With a trailer and total towing weight of 12K and keeping the speed around 67MPH I can get 14MPG on the outbound side and 16MPG on the return side when the trailer is only about 4,000lbs. The above figures are with optimum weather conditions and a tail wind.
You have 100K or so trouble free miles from a pickup and then it will literally $50 and $100 you to death. YMMV and luck of course. My 1993 has more $ in it than the 2003 is worth and it was all written off. (Survived the fun IRS audit acid test too.) Aka the 1993 earned it's restoration over 1/4 million miles and has the battle scars to prove it. Or was it more like an alcoholic owning a bar? :-laf
I think my '03 has right around $100K in it, which includes the purchase price including interest, all the fuel and maintenance costs, etc and excluding the insurance, registration, inspection, etc. My biggest single cost was $1700 for getting the front end suspension rebuilt earlier this year. That my get edged out when I get the HVAC doors and system done when I take it in to have the passenger and drivers side airbag recalls done. The AC works fine, but I go through a can of R134a every 18 months and one of my mode doors and the blend door have occasional problems, but still work for the most part. I've also had the APPS replaced twice, and am on my third windshield because of flying rocks and dying birds.