I was and still am very concerned my tool is too high a demand for most "affordable" inverters and thanks for the advice.
I will add the newer Peterbilt big trucks have factory-installed inverters that will easily run my tool---have used one and it works surprisingly well. Of course those trucks have 8-10 batteries and substantial alternators which might be the reason there.
I have considered wiring up a "jump box" with battery cable alligator or parrot clamps and connect it to my customer's trucks with engine running. The inverter input cables would be no more than 36" long, my tool cable length 10' or less. The tool is typically in action maybe 20-25 minutes each job. This idea would be temporary and as mentioned used as such.
My tools are fairly specific to my job and while Milwaukee manufactured are modified by another outfit so they accommodate their intended task. That outfit (Equalizer.com) doesn't really off powerful tools I require in a cordless configuration. I'll add the tools they DO have are of DeWalt manufacture that I consider pure junk in my trade.
Generator-wise I need an off-grid power source MAYBE twice a year so that's a big consideration. I'd own nothing but a Honda so having a $2K tool sitting around 99% of the year just doesn't sit well with me. Plus if I did own a Honda I'd immediately convert it to run on propane so there's another $300 +.
I might be able to test use a Kreiger 2K inverter already installed in a big truck---that brand mentioned only because one of my customers sells and installs that brand regularly. They're a full service mechanical shop and add or replace accessories like inverters quite often.
This just won't be easy will it?