Avalara Tax and Product Discounts Errors

[MattGore]

I've been using the Avalara system for several months now, but only just noticed this problem because it only applies to specific types of orders. Here's the problem:

1. Most of the products in my client's shop are non-taxable
2. Most of those non-taxable products have quantity discounts: 10% for 4+, 15% for 8+, 20% for 12+, etc. These are calculated and applied automatically by the plugin by iStraxx from the VM store (http://extensions.virtuemart.net/products/quantity-related-price-calculation-detail)
3. When the order information is passed to Avalara, instead of the discounts being applied at the line-level, they're applied (proportionally) to ALL lines in the order. So, if all of the lines in the order were taxable or not taxable, this would be fine... the amount of the discount still ends up being correct.

Let me give you an example:

Here's an order as it appears in Virtumart:

Quantity                       ITEM                                     Base Price               Discounted Price        Discount                     Total Price Before Discount          Total Price With Discount

5                                  (non-taxable item A)             4.05                        3.65                            2.03                           20.25                                            18.23
1                                  (taxable item)                       5.45                        5.45                             0.00                           5.45                                               5.45
1                                  (shipping)                              5.70                       5.70                             0.00                            5.70                                               5.70



This is how the order shows up as an Avalara Transaction in their Admin Panel:

#      LINE AMOUNT                          DISCOUNT                             NON-TAXABLE                  TAXABLE                  TAX

1       20.25                                      1.31                                       18.94                               0.00                        0.00
2.      5.45                                        0.35                                       0.00                                 5.10                        0.39
3.      5.70                                        0.37                                       4.20                                 1.13                        0.08

--------------------------Total Discount 2.03


So, you can see, the total discount is being passed through correctly, but because of the way that it is distributed across the whole order and NOT on a line-by-line basis, the system under-charges for sales tax on lines two and three, since  they're being mistakenly discounted.


I just spent an hour on the phone with Arindam Chakravorty at Avalara, and he ended up telling me that this was something that would have to be dealt with at the OEM level (specifically Mr. Milbers) ... they couldn't do anything about it, though they claim that it's an issue with the Avalra.php script.

Please let me know if there's any further information that I can provide to help get this resolved.

For what it's worth, I don't see a version number in the script (it says $), so I'm not sure if there's an updated version, but I did update my VM AIO to 2.6.6


Thanks for your help!

- Matthew