Make 3 copies of keys. One at the office, one zip tie under the truck, one to drive. MSDS in every vehicle
Fall safety and clean respirator in every vehicle
Extra nozzles, qc's, plugs, spray hose nozzes, garden hose, gas cans, box of latex gloves, marine grease, wand, o-rings, o-ring pick, 2 channel lock, razor knife, teflon tape, 6-1 nut driver, extra invoices, and possibly (hopefully) some warming jelly, and of course this is just a start.