Start with the exact chassis.
Bring the VIN for an existing truck or the complete order specification for a new one, plus bed or body dimensions, cab and door configuration, wheelbase or cab-to-axle details, and current manufacturer documentation for GVWR, front and rear GAWR, and payload. If the truck already has a body or equipment installed, bring its measured weight and axle weights when available.
Bring the mission and equipment list next. Document intended staffing, hose, reels, hand tools, fittings, PPE, medical or rescue gear, and anything else that must remain on the apparatus. Describe the response area, access limits, terrain, water sources, refill plan, drafting expectations, hose stretches, storage priorities, and whether pump-and-roll is required.
Verify, do not guess
Finally, bring the requirements that sit outside the skid. Include mutual-aid or resource-typing expectations, local standards, department SOPs, procurement language, and the people who must approve the purchase. If a number or requirement is unclear, flag it for verification. The meeting should replace assumptions with questions the department, chassis source, builder, and applicable authority can answer.