I came across an auction the other day that really made me laugh; it was a 5 Star Feedback Rating auction. Now this is not eBay legal and if you are a good seller you should not need to buy something like this!
Rather than try to buy a good rating, work on providing your customers with top notch service that will turn them into repeat customers.
First step is to have clear photos, and be sure to include photos of any flaws in your item. If you are selling something that doesn't work or is for parts only, be sure to add that to your title. Don't sell junk and don't say that something is in better condition than it really is.
Second step is to accurately describe your item. You don't need to tell a story, just offer the facts including measurements. This will save you from having to answer question for those buyers even willing to ask. Most people will just move on to the next listing if your description is incomplete.
Third, offer reasonable shipping costs on your items. You don't have to offer free shipping, and if you do make sure that you are building the cost into your price. What you do not want to do is to charge someone a lot more than the actual shipping. A small handling fee is fine, but you may get your stars dinged if you are really jacking up the shipping price.
Forth is shipping the item. Make sure it is well packaged and don't put breakables in an envelope. This may seem elementary, but you'd be surprised by the stories I hear from other sellers that have purchased on eBay.
Finally, consider including something in your package informing the customer how to reach you. I use a glossy postcard that I had printed in bulk. The card lets the customer know that I accept returns, that their satisfaction is important to me and how to reach me. This card has saved me from having customers open an Item Not As Described case which would give me an automatic defect. If the customer has your email address or phone number right with the item, they will most likely use it to contact you instead of opening a case.
For me, having satisfied customers is a great feeling. The 20% Top Rated Seller discount and the postage discount doesn't hurt either.