Developer to work with Quickbooks online APIS

We are a small company (2 people) trading organic fruit. We are currently using Quickbooks online to manage our orders and financials but need to add some features that do not exist in a current add on app. We are seeking for a developer to work on their APIS and create the fields we need to make the system better suited for us.
Rate depends on expertise so please let us know if this is something for you and we can discuss further on the hours needed and fee once we have a match