Couple of Shipping Questions

Hi,
Thanks in advance for taking the time to try to help me. I have a childrens boutique and I am going e-commerce very soon, but in the meantime I am selling excess webkinz inventory on ebay. I am trying to figure out the best overall shipping solution for immediate and the future. What is the best way to ship various items. I shipped out a couple webkinz in tyveck envelopes I happened to have on hand. The shipping calculator was high compared to having them weighed at the post office. As for the store, I mostly sell sets rather than pieces of clothing so I :)think boxes are going to be the best way to go. How do you cover yourself and still have flat rate pricing but stay fair to the customers. Where do you get the boxes and how do you cover the cost of shipping? Who is the best company to ship with? I was on the overnight media website and is this a good option?
Thanks for your help.

Using boxes than envelopes is always the better choice - it reflects a higher level of quality in my mind.

i agree, i thinkg going with the boxes will say alot of a company rather then envelopes.

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