If you are using Cart Level Discounts or automatic promotions, you'll need to account for these when quoting. They take precedence over the pricing we set in the cart in many cases.
We do our best to show warnings when we detect them, but this is not always feasible with the API routes provided by BigCommerce at present.
BigCommerce has no mechanism for any developer to identify cart level discounts. Their logic on discount rules is also "baked" into their platform to where we can't make overrides... (More on that below..) Rest assured, we're working on a way to at least identify when they're active and let you know, but it's a quite difficult problem, and still a work in progress..
The good news is that there is a glimmer of hope! BigCommerce currently has a promotions API in beta, and we hope it will help at a minimum detect when a store has promotions enabled so we can better alert reps of potential conflicts.
As of August 2020, the BigCommerce promotions API is still in beta.
We find that our B2B customers tend to use Automatic Promotions sparingly, and so this is typically not a major issue for our customers.
If in doubt, you can always test your quotes. Keeping in mind that quotes are customer specific, and promotions applied to non-retail customers may not show when testing as a retail customer.
Also keep in mind that Automatic promotions can be limited by customer, customer group, category, brand, product, etc. They can also have expirations, and influence one another based on the processing rule settings. Much of this logic will only be known by the person or team that set these up for your store.
It's imperative that you communicate the current promotions, and the rules setup for those promotions with your quote team, so they can be sure they don't inadvertently extend extra discounts on top of the Promotions.
See below for the logic on how discounts are applied to quotes within BC.
The below is cut and paste from this support article explaining the order w/ which discounts are applied. It has been changing with the addition of price lists, and new promotions, so be sure to check out this page for the most up to date info:
Order of Operations
If you have multiple discounts running at one time, the system runs them with a specific priority. See below to learn which discounts are honored first.
NEW STORES (CREATED AFTER JULY 2014)
Cart-Level Discounts - Product Rules
Cart-Level Discounts - Order Rules
Customer Groups
Option/Option Set price change rules
Bulk Pricing discounts
Product List option/bundle price changes
Coupon Codes
OLDER STORES
Cart-Level Discounts
Option/Option Set price change rules
Bulk Pricing discounts
Customer Groups
Product List option/bundle price changes
Coupon Codes