@bbg06 eBay labels are almost always going to be the lowest cost. Definitely lower than buying at the counter of the carriers.
Make sure you have correctly entered the weight and dimensions. Anything larger than 1 cubic foot will almost certainly incur dimensional weight pricing where the carrier charges for the volume (the space) the package takes up instead of the weight of the package. There are also special surcharges for special shaped items, like cylinders, among other things. Both dimensional weight and the special surcharges will apply no matter where you get your postage, if they are applicable to what you are shipping. You may also double-check the service. If you are shipping priority, airmail, express, etc., the charges go up significantly. Depending on what you are mailing and size of the package, it may qualify for economy shipping which will be cheaper.
FYI...you must always round up in the measurements if you are shipping FedEx or UPS. For example, 9.1, 9.5, and 9.7 all round up to 10 inches. For USPS, you may round down if it is below the 1/2 inch mark, meaning 9.4 rounds down to 9 inches. You round up if it is at or above the half-inch mark, so 9.6 will round up to 10 inches.
To help get the size and thus the price down, you can cut the box down. Sometimes you can save several dollars or more by doing that.
