On the flip side, I am so close to finishing it. so far, I was able to:
1. Correct the Cart total based on the subtotal and add the extra fee
2. update the details page of the cart during checkout to display the extra fee and display the adjusted total
3. Pass the corrected total to PayPal
All I need now is to filter the extra fee if it is UPS shipping or if it is a Greenhouse pickup, which has a pickup location ID. I used the OrderTotalCalculationService.cs to make the adjustments. Since I am selecting a pickup location or UPS shipping before I calculate the total, I am pretty sure there is a way to look for the type of shipping being requested and decide whether to charge the extra fee or not... Any ideas how I can check for that right here?
var discountAmountInclTax = discountAmountExclTax;
//subtotal with discount (excl tax)
var subTotalExclTaxWithDiscount = subTotalExclTaxWithoutDiscount - discountAmountExclTax;
//calculate under $20 extra fee
if (subTotalExclTaxWithDiscount < 20)
subTotalExclTaxWithDiscount += 2;