Two offers can show the same unit price and still lead to different total costs. Start with the quantity and specification you actually intend to buy. List product cost, customisation, packaging, sample charges, transport and any handling or inspection services you choose. Note which amounts are confirmed and which remain estimates; keep the supplier’s quote and the date beside your comparison.
Ask who is responsible for each stage of delivery and which charges are included in the quoted shipping amount. Destination charges, taxes or duties may depend on the shipment and location, so request an explanation from the relevant provider rather than assuming they are covered. Compare offers in the same currency and note the exchange rate and date used. An estimate can change before the order is placed.
Divide the comparable total by the number of units you expect to receive, and consider the effect of packaging size, delivery time and usable quantity. Keep uncertain charges visible as a separate allowance. If a low headline price depends on a different specification or quantity, ask for a revised quote using the same brief before choosing.