Hello, I have been working with Odoo for several years, started with version 8 and I have experience developing custom modules for different types of business. I have also worked customizing and implementing modules of Accounting, Billing, Inventory, Sales, Purchasing, Payroll, CRM, Point of Sale, websites. I have made modifications in the functionality of the modules, in addition to changes in reports and screens.
I have developed a module that read an xml file and create the invoice on odoo, i think it's similar to your requirement. This module reads an directory on the server where you can put the xls files and the module create the invoice, the process is automatic.
I also have experience with installations on AWS and Ubuntu.
I would need more information to be able to refine the quote, as well as some other details. Any questions I am at your service, contact me.