I started an eBay store called Blue Turquoise in March 2006, so I consider myself still pretty "green". I am always learning. Today, I made a very expensive mistake that cost a sale. I want to share what I have learned so that others will not make the same mistake. I listed an electronic keyboard (full-size) and chose UPS as the shipping option. I thought UPS Ground would be the most cost efficient and timely way to ship and felt comfortable knowing they can handle a large item. So a buyer used the "Buy It Now" feature plus the shipping calculator and was quoted half of the cost of actual shipping. The buyer and the UPS quote were as only accurate as the information included  in my listing because I listed the weight of the item only. My point is that I did not do my homework and have an idea of how much the total weight would be after final packaging. Nor did I know that there is a packaging fee for UPS to prepare the item. Being new, I couldn't afford to absorb the packaging fee (which amounted to $27.13) plus the total shipping ($43.83 instead of what my buyer was quoted at $25.11).  I have learned how important it is to take your time and fully prepare a listing before it goes on eBay. Know what the item is going to weigh at shipment, you can do this by obtaining a quote using any shipping service. I find it most helpful to physically take the item into the store and let the staff measure it--guesswork eliminated!  I think my mistake damaged my credibility, not to mention destroying a potential repeat customer opportunity. Putting myself in the buyer's shoes, the sale had lost legitimacy. By taking your time and getting quotes prior to listing an item, you come from a position of strength. They say if you learn one thing from your mistakes, how could it be a failure? Good luck & Happy Listing!!!