I use USPS only through eBay. No handling or materials fees.
U.S. Buyers:
First Class: Up to 15 oz.
Priority Mail: 15 oz. - 2 pounds
Parcel Select: 2 pounds & over
I also include a Priority option on all Parcel Select packages
International Buyers:
First Class: Under 4 pounds
Priority Mail: Over 4 pounds