Product Quantity by Location/Warehouse

[balihr]

Have multiple locations for physical stores and would like to share quantity from each store with site so qty field get total qty available to ship.

qty1 and qty2 are being used to show availability of actual qty on each store, plus using these fields to send data to Google for local pick up/physical stores.

In future plan on using qty 1 and qty 2 fields to show delivery date per customer location to offer faster delivery options.

IMO, you'll need to get your hands dirty and get the coding done. A simple approach would be to add 2 more fields (let's say qty1 and qty2) in the database and add logic to update products_quantity based on the values in those fields. Javascript can do it in admin product page.
As for frontend, you'd need a new function that would be called during checkout_process - you could for example use NOTIFY_CHECKOUT_PROCESS_AFTER_SEND_ORDER_EMAIL notifier to get this part done. This would be a bit more fun because you need to run through all products and be careful not to go into negative values (for example, qty1 is 2, qty2 is 5, ordered 4).
Using these fields for Google will require your GPSF module to be modified, just like you'll need custom code for delivery dates per location.

Don't forget to handle cases in admin when order is cancelled or deleted and you need to restock.