Early modern markets were characterized by a high level of uncertainty. Products were not standardized, their manufacturing or transforming generated wide ranges of qualities, made even broader by shipping and storage issues. The result was a complex universe of goods distributed along price/quality scales, associated with an equally diverse number of brands. Means of payment were as uncertain, with even the value of gold- and silver-based metallic currency in doubt, and few significant attempts at developing paper money. Most transactions were realized on credit anyway, with a significant risk of default; formalized commercial paper did circulate through endorsement, and traders massively used book credit, providing banking services through book transfers between their customers. Most of the monetary mass was made up of these book credits and commercial paper, with a constant risk of failure and credit crunches. Delayed payment was the norm, and the object of complex, partly socio-culturally constrained negotiations with debtors. Traders also had to negotiate with customers, faced with goods of unknown qualities, so that the latter would accept the proposed price/quality combination.