I'm getting a weird error at the total... it appears to be adding one field to the total twice. If remove a different field, the error goes away.
User selects Buyer Type 1, Buyer Type 2 or Buyer Type 3 (Radio Buttons)
There is a product.
There is a product, but used for shipping (flat rate per item)
There is a product, but used for sales taxes (conditional based on state & buyer type. Must be buyer type 1 and in a particular state).
If Buyer Type 1 is selected AND the correct state is selected, the Sales Tax calculation is run (and shows correctly).
Shipping is calculated (quantity of product * a flat rate number). This is correct.
WIth a quantity of 1, all calculations are correct.
With 2 or more quantity, things go wonky. The product price is $6.99, flat rate shipping is $5.00 per item. With no taxes, it's $11.99 for 1.
For anything more than 1, the pattern is Product * Quantity * Quantity + Shipping * Quantity + Sales Tax.
If Buyer Type 2 or 3 is selected, the total calculation is correct regardless of quantity.
I've looked at the exported XML and I don't see anything strange. I've tried opening the form in different browsers and the error still shows up.