BigCommerce App Developer Needed - to be able to reprice, delist products 2-ways, and use external APIs to update products.

I am looking to discuss a project with a BigCommerce developer who would be able to help me build apps that would help integrate into a custom software (that I do not own) and pull info from my accounts on that software. We list 1000s of items using the software described above to Amazon and we're looking for an effective way to use BigCommerce as our own marketplace. We want to use a 'headless' version of BigCommerce powered with WordPress as the frontend and then use BigCommerce for managing products, syncing stocks, resyncing prices, and then also pulling in additional product information. We need the system to be able to communicate with our custom piece of software to remove stock in real time when it sells on another platform. We have API endpoints that we are currently using to accomplish this with our Wordpress/WooCommerce build, but I want to achieve this with BigCommerce in hopes of having a more stable platform. In addition we are looking to potentially import data from an iMDB movie database API and also an ISBN movie database API. We may also need an automatic tool that will allow for automatic imports of inventory from our custom software via a CSV. This CSV is accessible via API download as well. I'm looking for a BigCommerce developer who can help tell me what is possible and whether BigCommerce is the correct platform for me to achieve this on. We have our own site, but we have many other clients who want to work with us on building similar sites out and we would like to make this platform something we can repeat. We are also talking about using the Enterprise version of BigCommerce and having a large marketplace of many multiple sellers on Amazon who can create a type of 'competition' site using BigCommerce for several dozen sellers combined inventory.