Need Advice with Shipping

I have a dillema on my hands.
My new cart ChristianBazaar, is finally up after a couple of months of dabbling, and I'm still at it.

At the moment, the shop is in showcase mode.
The supplier that drop ships for me does not have a method for supplying shipping weights for the items in their catalog. They seem to want to do e-commerce without the "e-" part.

They ship with DHL and bill me together with the order.
I also want to estimate shipping based on DHL rates, but have resigned myself to UPS rates, and ship with DHL.

What I can't figure out is what to do when you don't know the weights with any certainty. Can you guys share some strategems for shipping under these circumstances? Consider the balance between profit loss avoidance vs. blowing away the sale with over zealous shipping rates.

Here are a couple of options:

1. add 5-10% to your items prices and ship at a flat rate
2. guessetimate the weights of the items and revise as you learn the actual shipping weights

Shrimp-Gumbo

guesstimate the weights of the items and revise as you learn the actual shipping weights

Even though I have my items in-house rather than drop shipping, this is what I am doing. Between using various packaging and including a free gift, I had to guess when setting up the weight table, and I'm adjusting it as it turns out the shipping was significantly too high or too low.

If you guesstimate be sure and not let you customers see any weights for items. If you do, you will come across somebody who will weigh their item and complain about it.
:yuck: