How do contracts and payments work for shipping services?

Roasters have a contract with Algrano, and will pay Algrano the FOB value plus the costs to ship it. Algrano has a contract with exporter, and will pay the FOB value to the exporter. Finally, the exporter will sign a contract with the producer, and will pay the agreed Farmgate price to the producer. There is full transparency on all costs from the farm to the roaster.