USPS domestic flat rate box I see it for international

[stuffdone]

This would be a good add-on that would not require any USPS server because the shipping cost for flat rate is fixed at a known amount.

It would not work with the API because there is currently no way to transmit dimensions to know which box a particular item would fit in and no way to judge when it would not fit in any available flat rate box regardless of weight. Also if you ship over seas the weight limits are much lower.

A work around could be to set up a flat rate attribute and apply it to specific products based on the size box needed. Set shipping weight to zero.

Zen has some specific limitations on shipping calculations that are hard to work around.

I use a drop shipper and I don't ship but I still need to charge for shipping even though I can't control the method the shipper may use. With no means to match physical dimensions to a flat rate box you are stuck with regular postage rates based on weight which in almost all cases will over charge customers for items you send flat rate.

If you add an attribute to account for flat rate there is no way to turn off additional shipping calculations on a per-item bases so it does not calculate for those items.

An ideal add-on or feature for future releases would be to assign individual products to a specific flat rate box and bypass other shipping calculations.

Hint


Also limiting flexibility, a per unit or per item shipping added at check out has no way to adjust for product weight. A 1 pound bag of feathers costs as much to ship as a 80 pound bag of lead.

Zen needs more work on shipping options so specific items can have their own shipping cost that are not affected by automatic calculations. This could be an over-ride to meet specific needs such as flat rate boxes or to apply a per-item rate based on that particular item's weight.