Automated Rule for comparing 2 or more shipping options and choosing least expensive.

We ship using FedEx, UPS, and USPS.
It would save us a huge amount of time and money each year if each order would automatically pick the cheapest shipping option between selected carriers.

For example:
1. Order # 1234567 for a "blue widget" gets imported into SS with dimensions 8" X 6" X 4" and weighs 11lbs

1. Automated Rule checks price for FedEx Home Delivery, UPS Ground, and USPS Priority mail Package.




2. FedEx: $12, UPS $12.50, USPS $11.50




3. Order # 1234567 automatically gets assigned to USPS Priority Mail Package since it's cheapest.

This information already exists in SS, but it requires manually changing between each shipping service. This is impractical especially when a business ships thousands of order per month.

Thanks!