Whether you are new to eBay or an established member, your reputation is arguably the most valuable asset you have. Your "reputation" is based in part on how long you have been a member (this mostly applies to members who have had their accounts or user IDs for less than 30 days), but more importantly, your feedback score. The feedback you recieve and leave for others can speak volumes for or against you, and understanding exactly what those numbers and percentages mean can save you a lot of time and trouble.

Some buyers have been frustrated by the increasing number of sellers who refuse to accept bids from buyers with a feedback rating of "less than 10" or "any negative feedback".  Some sellers have been burned by uncommunicative or unreasonable buyers who post negative feedback on transactions that could have been resolved privately.

Retaliatory feedback is the single worst thing you can do on eBay ( ... well, besides being a con artist or failing to complete your end of a transaction!). Many times, it is self-evident reading an exchange of feedback between a buyer and seller not only what kinds of personalities are behind the scores and comments, but the ugly fact that feedback has been used to do a buyer or seller's reputation harm when basic understanding of the process of transacting business on eBay and common courtesy would have sufficed and left both sides much happier.  In other words -- leaving feedback is a power not to be abused. A nasty comment can backfire and make you look like the party who was in the wrong. It can even cost you your eBay account.

Here's a quick and simple guide to making the most of your transactions, building a good reputation for yourself, and recognizing the red flags to avoid in auction listings and buyer/seller feedback ratings that may lead to a negative experience.

BUYERS:
It's no secret that it is easy to get carried away on eBay. Finding that "just right" item and the anticipation of bidding against others is all part of the game, and should be kept in perspective. The most important thing to keep in mind as a buyer are:

1. NEVER bid on an auction without reading the entire listing. Most sellers have specific terms of sale to which you automatically agree if you place a bid.
2. Check the seller's feedback before you bid.  Click on the feedback score next to their name and view the percentage of satisfactory transactions they have completed. A satisfaction rating lower than 95% calls for close scrutiny of the seller's feedback comments.
3. Don't automatically assume that a seller is dishonest if s/he has a negative feedback.  Read the comments left on the "negative" transaction/s.  Cross-links to the other party's feedback are usually available, and can give you a lot of insight into what really happened.
4. Remember that there are millions of people on eBay, and not every personality and expectation is going to be a happy match.
5. Get a confirmed shipping price BEFORE you place your bid. If a price or calculator is not posted within the auction listing, contact the seller via email and ask for a quote. Remember, those brand-new 99¢ shoes aren't the bargain you're expecting if you end up paying $50/each in shipping charges.
   
6. Make sure you understand and agree to the seller's terms of sale before you bid. Pay attention to what is promised and what is not; what disclaimers are presented and what is not stated. If the seller states that they ship within 7 days of receipt of payment, it is unreasonable to expect shipment the day the auction ends.
7. Don't hesitate to contact the seller if you have questions about the item up for auction, questions about the seller's terms of sale, or if you would like to request an exception to the stated terms of sale.  For example, if a shipping fee seems completely out of line for a particular item, try asking the seller if they would consider another shipping option. Sometimes sellers don't realize there are less expensive options available to them, and they are happy to comply with your polite request.
8. Courtesy and respect pay off!  If you are unhappy with an item, contact the seller directly and give them the opportunity to make it right before you post negative or neutral feedback. Communicate professionally and reasonably, and most sellers will go out of their way to make sure you are satisfied.
9. If you are conned or feel you've been ripped off, you have recourse.  Use it fairly and judiciously, but don't be afraid to use it!
10. Contact the seller as quickly as possible after you win their auction. This can be in the form of a confirmation email acknowledging your win and promising a time and method of payment, or if you use an online payment system such as Paypal, simply pay for the item.  The seller will be notified that you have completed your end of the transaction.
11. Never allow more than 30 days to lapse on an auction you have won without taking action if you have not received your item or the seller will not communicate with you.  You cannot file a complaint with eBay until 30 days from the date the auction ends, but if you have used Paypal to pay for the auction, you only have 30 days to request a refund for non-delivery.  Always try to contact the seller first.  If that fails, request a refund through Paypal, and after 30 days, file a claim with eBay for non-delivery.
12. Once you have received your item/s, post feedback to the seller promptly.  This not only makes them aware that you have received your item/s -- it also indicates that you are satisfied and the trasnaction can be considered concluded.  The seller should then post positive feedback in return. (Some sellers do a LOT of business on eBay every month, and it takes them time to get all their feedback posted, so be patient.)

SELLERS:
The most common issues sellers face are communicating effectively to ensure a positive experience for the buyer, shipping and handling costs, developing clear and concise terms of sale, and dealing with the buyer who "just can't be satisfied."  Here are a few tips and tricks to make your auctions stand out both in search results, and as clear, honest auction listings that reflect your integrity as a seller:

1. Terms of sale.  Before you post your auction, give careful through to the terms of sale you are comfortable promising, and state them plainly.  Ask yourself how quickly you will require payment.  What forms of payment will you accept?  Will you ship internationally? Will you allow local pick-up at no charge? How quickly can you ship once payment has been received (hint: the faster you ship, the more repeat business you are likely to generate)? What is your policy on returns? Who pays for shipping on returns, and how much of the total price of the auction (including shipping charges, insurance, etc.) are you willing to refund if you offer refunds?  Will you charge a handling fee, or charge your buyer back for the fees you pay for accepting online payments such as Paypal? There is no absolute right or wrong when it comes to individual terms of sale. It is, however, a "best practice" to spell everything out clearly and leave nothing to the buyer to presume or guess at.
2. Listing your item/s.  There are three key elements to a good auction listing: honest and detailed description/s of the item/s, clear and detailed photographs, and using the most effective wording in your listing headline.  In your description of the item, include details such as age, size/dimensions, color, brand/manufacturer and model, a honest assessment of the condition including mention of flaws or damage. If you are selling wearables, what is the size and the measurements? Is the item new? Like new? Is it a factory second or close-out lot? What kind of fabric is it made of? If you are selling jewelry, don't try to make a gold-plated CZ sound like a 14k gold 1 carat diamond ring. This only casts doubt on your credibility -- as does the use of ambiguous terms such as "genuine lab created" for synthetic gemstones. Your listing may be technically honest, but if what you're selling hasn't been clearly and plainly defined, you run a high risk of damaging your own reputation through disappointed buyers.
3. Photographs.  Clear, detailed photos of your item are crucial to generating the greatest interest and the highest potential bids. Common mistakes that have a direct impact on the number of potential buyers viewing your listing as well as the final sales price are cloudy/fuzzy images, too dark or washed-out images that show no detail, not posting enough pictures to adequately portray the item/s from every necessary angle (sometimes that means one or two images -- sometimes it means 10.  This depends on the item, but a good rule of thumb is "more is better"), and failing to take into account the backdrop or background and how the item is presented.  For example, if you are selling a $400 suit, don't lay it out flat on your living room carpet and post an out-of-focus picture expecting to make more than maybe $50 on the suit.  Ideally, clothes, shoes and wigs should be displayed on manequins, and should be pinned or at least positioned "naturally" rather than flat.  If you don't have a manequin, it's better to hang the item on a hanger and carefully pin and position it to present well.  (Dip one cuff of a jacket into the pocket, for example, to make it easier for the potential buyer to visualize themselves wearing the item/s.) It's best not to use live models. For one, you can't sell an item as "new/never worn" when it is clearly on a person's body in the photo.  Additionally, people do like to be able to envision themselves in or with the item, and another person wearing or using it detracts from that and makes the item look used (and therefore less valuable).  So make sure the pictures you post are clear and detailed, show the item/s from all necessary angles, show them off rather than just laying them out flat, and don't conceal flaws -- expose them! Finally, be sure to crop out any extraneous background. Nothing looks tackier than a product shot with a towel as the backdrop, and the living room floor all around the towel. Crop out the extra background so only the backdrop you've selected shows.
   
4. Use the gallery/thumbnail feature.  Select your best image, and make sure you include a thumbnail of your item with the auction listing.  You'll attract substantially more interest.
5. Setting your price.  This can be tough -- especially if you have no idea what the item is worth, or your sentimental attachment to it makes it more valuable to you than it is in the marketplace.  To price your item competitively, do a search for similar items and note what they are listed for (and what they're selling for -- often two different amounts).  Check other sources as well such as froogle.com to get the best overall picture of what this item should sell for.  If you must get a minimum amount or you don't want to sell, set a reserve price at that amount and open the bidding at a low price to encourage bidders to take interest in your auction.  The more invested they become in the auction, the more likely they are to want to win it and raise their bid!  If you want to sell at an absolute set price, use the "Buy it Now" option.  If you really want to sell the item, start it at a very low price with no reserve.  Just know that if you do not set a reserve price, the item will sell to the highest bidder at whatever the final price turns out to be.
6. Communication.  Once your auction is posted, be sure to check your email for questions from potential buyers, and answer them promptly. If you are asked to accept alternative terms to those you have stated, consider being flexible. If the request is reasonable, there's no harm in agreeing, and it may make the difference between selling your item or having to relist it.  After the auction closes, be sure to contact the winner within 3 days of the close of the auction -- whether you have heard from them or not.  Just a friendly reminder or congratulations will suffice. If you have cause for concern that an auction is not going to be paid, a bid was fraudulent, or you are going to have a problem with the buyer, immediately document everything you do and say in your efforts to politely and professionally close the transaction. 
7. Shipping.  Another very touchy point for lots of folks. This is only my opinion, but it's just bad business to deliberately price your shipping to guarantee you make money on your auction. Shipping charges should be reasonable and fair -- to you as well as the buyer.  eBay allows you the option to include a shipping calculator in your listing, and this is a good practice.  You can build your $5 handling fee into the price and/or specify which shipping services you choose to offer.  Before you post your auction, make certain you have verified the actual shipping costs if you are planning to post a flat rate price.  Many sellers aren't aware that the USPS offers free packaging, boxes, labels, and tape, and they will deliver as many cases of materials as you request right to your door for free!  Take advantage of "flat rate" priority mail boxes.  These are boxes of various sizes that can be of any weight and always ship for the same flat fee -- usually around $5.  USPS will also pick up priority mail packages from your front door at no charge, so you can save yourself the time and gas as well as a trip to the post office.  Don't forget to consider offering the "media mail" option for books and magazines.  This is a HUGE money-saver, and can also make the difference between an item selling and having to be relisted. Likewise, keep in mind that if an item is bulky, odd-sized, oversized or heavy, shipping is going to be substantial, and you will probably need to purchase special shipping materials. Be sure to account for these before you set your shipping price. You may even want to add a blurb in your listing about the price of the shipping and why it is what it is.
   
8. ALWAYS live up to your terms of sale. If you are going to be a day late shipping, drop your buyer an email to let them know. If you have a dissatisfied customer and your terms state that you will accept returns under "x" conditions, honor them promptly and courteously.
9. After the sale.  Many sellers like to slip a note into each outgoing package thanking the buyer for their business and asking them to contact them directly if there are any problems or dissatisfaction with the item/s.  This is also a good opportunity to remind your buyer that you would appreciate their positive feedback upon receipt if they are satisfied, and you will post positive feedback in return when you know they have received the item and are fully satisfied.
10. Post feedback promptly.  Once your transaction is successfully concluded, be sure to post positive feedback for the buyer promptly.  This is not only a professional courtesy -- it encourages the buyer to do business with you again and increases their level of overall satisfaction.  When you leave feedback, find something genuine and meaningful to say.  "Great!" is not useful feedback for your buyer or anyone else. Even if you post the same positive feedback to every good customer, it's a courtesy to make a useful comment such as, "Immediate payment. Great buyer. Thank you for your business!"
11. The seller who can't be satisfied.  It happens to the best of sellers. Do your best to make the situation right. Communicate, communicate, communicate ... and document everything. Above all, if negative feedback is left for you, don't retaliate. Post factual and courteous response within your own feedback, and let your character stand as the loud voice of reason in the transaction. Some folks just aren't worth the ulcer, you know?

eBay can be a wonderful, positive experience and a great place to pick up unbelievable bargains. Following these tips will help you post a more effective listing and attract more potential bidders as a seller, and ensures you will have safer, more positive transactions as a buyer.  eBay is a community built on trust.  Your feedback rating is a direct reflection of your trustworthiness, and is your signature and biography.  Protect it by communicating first, and taking negative action only as a last resort.