Update Shopify Facebook and Instagram Stores based on Ebay Inventory list

We have 2600 Articles on eBay, we want somebody to do a process to connect them to the Shopify store ( already created) then update Facebook and Instagram store which are already created too.

We need to Improve apirience and make it profitable.
Looking for somebody who can propose a plan of action so we can expand out sales that actually are been done only on eBay.
www.CWretailsales.com @cellularwholesales
Our budget is really low since we have paid for this service 3 times and so far nobody had done a good job and the store is not selling and not updated.
Please send proposal and cost for us to evaluate.