PostgreSQL Ecommerce Database Setup

I’m launching a fresh PostgreSQL back-end and need it designed from the ground up to power an ecommerce workflow. The database must comfortably store products, orders, and payments, with the first release focused on the payments, refunds, and full transaction history module... (Budget: $250 - $750 CAD, Jobs: Database Administration, Database Design, Database Development, Database Programming, eCommerce, MySQL, PostgreSQL, SQL)