It's more about how you buy than what you buy. Then about how many you do over how little you do.
For instance, I was talking last week with my daughter about my running cost(s) on my trucks when I was operating my towing business from 85 till 2003. I had it down in the end to 52.7¢ per mile. Now that was with EVERYTHING, my cell bill, pager bill, tires, brakes, oil, fuel, insurance, bank fees, cleaning and washing, (both the truck and my clothes), even the 'gifts' I gave my accounts a few times a year, like when I'd show up with donuts or hams and food during the holidays.
That was also figuring in by then I wasn't driving NEAR as many miles per year as I did when I started in 85. For the first 5~6 years I averaged about 75,000 miles a year. The cost per mile there was much less, but then again my first rollback wasn't but $22,500 and my last one was $80,000. (And to buy one outfitted the same these days it'd be easily $125,000.
The thing is, guys are always out there wanting to undercut your towing rates (let's say for dealer transfers) and quote $1.00 a mile (back then). Keep in mind you only get paid ONE WAY. So what they didn't understand was that they were PAYING THE DEALERSHIP for the honor of towing their cars for them. I wouldn't touch anything for under $1.75 plus a loading fee, because I learned that I didn't need to go in the hole with the truck moving when I could sit still and do that. :laughing:
So yeah.... buying in bulk hurts up front, but it'll save you a ton down the road. Just need to have enough business to pay for the 'down the road' part.