Samples are normal practice and usually inexpensive, but they only protect you if you make them contractually meaningful. The common structure is that the buyer pays courier costs and often a nominal sample charge, frequently credited against a first bulk order — a supplier refusing any sample on a commodity is a signal worth taking seriously. The critical step most buyers skip: state in writing that the bulk order must match the approved sample, and keep a retained portion of that sample yourself, sealed and dated. Without a retained reference there is nothing to arbitrate against when a consignment is disputed, and the sample becomes decoration. Understand the limits too. A sample proves what the supplier could produce once, not what they can hold across a production run — which is why a sample is a screening tool and pre-shipment inspection is the actual control on a bulk order. For agricultural goods a sample is also seasonal: a crop sampled at one point in a harvest can legitimately differ later, so tie the specification to measurable attributes such as moisture, grade and defect tolerance rather than to a visual impression. Budget around USD 150 to 300 for an independent pre-shipment inspection on the bulk order, and commission it yourself so the report is not one the supplier controlled.