Create Database in Big Query for ecommerce business

We are looking for help to design and build a comprehensive data warehouse using Big Query to store all our company data ideally using free/open source ETL like Airbyte:

• Sales for all channels (Amazon, Shopify etc)
• Ads expenses for all channels as well as Google and Social Media
• All channel related expenses (fees, storage, fulfillment etc)
• Inventory and stock levels (either directly form channels or via Linnworks WMS)
• Shipments tracking including all costs

The data ideally should be pulled directly from channels so connections needs to setup to all main channels either using prebuild services or API

Once data is created we need BI/Looker dashboards to display:

Sales by Channel + Total Day, Week, Month…

Sales by Item

Sales by state

Advertising Spend + Return on spend

Marketplace fees and all costs going into Gross Margin

New Customer Reviews + trend - up/down

profitability and rolling item costs (By adding any changes In market conditions - Container Rates, Import Duties, Drayage Rates ETC…)

New Customer Support tickets + Customer Response Time

Hours worked/by department

Budgets and Budget Tracking

Shipments Inbound

Accounts Receivable

Accounts Payable

Cash in Accounts

Inventory & Value at cost + Value at Gross Sale…

ROI on certain projects and New products

Product start ratings and trend all countries.

Upcoming campaigns, Deals, TV Events (edited)

Result should be very similar to capabilities of Seller Board software

Contract duration of 3 to 6 months. with 30 hours per week.

Mandatory skills

MySQL, BigQuery, API, Amazon Seller Central,