Create a Quickbooks API integration using data queries (provided)

We have a PoS software and need to have a Quickbooks integration. We are very busy and so instead of investigating the API solution ourselves we would like a company to write the API for us, in Java. We will provide access to the database and the queries that need to be included, and need a fully finished API integration for pulling this data (for example user data for payroll, hours worked, items sold, purchase order lines) that we can deliver to customers. We anticipate that more work would follow in the future as new features are added (and also we have another software package that could need an API). However, we need to receive the complete source code and instructions with this project so that we have everything needed to develop in house should we need it.