Since hydraulic supports are often custom-engineered for specific seam heights, negotiate a phased payment schedule (e.g., 30% deposit, 40% after successful factory pressure tests, 30% after delivery). Demand a detailed production timeline and include liquidated damages clauses for delays exceeding 15 days, as mining downtime is extremely costly. For bulk orders, aim for a 10-15% discount on the unit price by consolidating the purchase of spare parts (valves, seals, hoses) into the initial contract.