[thelist] drop shipping and shopping carts

[chris]

Hi,
What are folks using for drop shipping carts? Shipping is the biggest
bugbear that I need to solve and I'm not finding it. 

- I need to configure shipping from the drop shipper both as a flat rate
and calculated for USPS and UPS or FedEx.

- if the item's shipping is a flat rate, when multiple items are ordered
from the same drop shipper, the shipping rate needs to not append to
each order. IOW, the owner wants customers to be able to order a widget
that has a flat rate of $6, and if they order 2, the rate should remain
$6, rather than $12.

- cart must integrate with 2checkout.

- for my sanity I prefer a cart that has at least 1 tableless
template ... but that's probably too much to ask.

thanks for any insights.

-chris

P.S. The site currently uses xcart so if you recommend xcart, please
point me in the direction of how to solve the above requirements in it.
xcart only allows 1 point of origin address.