International trade routes revealed comparative advantages of the different shippers, whether New England or British. Merchants dealt with shippers with whom they had a history. Knowing market conditions was easier for local merchants. Crews were paid less in their home ports.
The Colonial monetary situation included wampum which was used by the Dutch in the purchase of Manhattan. The British bimetallism system of a 15:1 ratio of silver to gold was in force, but gold was little used. Gresham's Law played out and the undervalued silver disappeared. Paper warehouse receipts for tobacco served as money as did alcohol and musket balls. Silver pieces of eight equaled one dollar. There was not really a shortage of money in Colonial times.
Lecture 5 of 9 from Mark Thornton's The Economic History of the United States.