The order and tracking synchronization will still work even if the order is a mixture of items belonging to different locations (Turn 14) or (local). The Turn 14 app will only extract the item that belongs to it.
Same thing with live shipping rates! It will work even if an order is a mixture of items belonging to different locations.
Below is an example of 2 items.
ACC11369 Access Original 15-20 Ford F-150 5ft 6in Bed Roll-Up Cover (Hatfieild location - local)
BAJ257815 Baja Designs Squadron Wide Cornering LED Fog Lights Pair -Amber (Turn14 Distribution API app)
An example of checkout of local item ACC11369 . Notice that it is free in this case and 5-8 business days.
An example of checkout of Turn 14 Distribution API app BAJ257815. Notice the live shipping rates provided by Turn 14.
An example of checkout of mixed items ACC11369 and BAJ257815. Notice that the shipping cost are added up and Shopify will only show 1 rate with a name of "Shipping"
Shopify will use the cheapest from Turn 14 Distribution app which is 14.32 and then add to the free from local. The end result is still 14.32.
Then the 5-8 business days will be the longest.
We would highly recommend that customers create a development store and try this out so that they are comfortable before using it in a live store.