I don't really consider this a guide, but I want to share my personal story on how I learned to spot fakes within 3 seconds of looking at an eBay listing.
When I decided to purchase my first pair of 7 For All Mankind jeans, I decided where better than eBay? I think I paid a whopping $45.00 for the traditional bootcut in NYD. After a lot of research, I found these rarely, if ever, go on sale - anywhere. So I chalked that one up to stupidity and decided to search internet sites (which will remain nameless - Luleeta) for discount 7 For All Mankind jeans - this was at Christmas and I have 2 sister-in-laws that would kill for some nice jeans. I found this "GREAT" site where they had all kinds of nice jeans for about 1/2 the price of retail. I purchased 7 pair of "100% GUARANTEE AUTHENTIC 7 FOR ALL MANKIND JEANS" from this website. I paid approximately $89 - $99 / each. Now in my opinion, this is still a great deal on a new pair of 7's. They offered a money-back guarantee, so I figured what is there to lose?
Between the time I ordered the jeans until they arrived, I did my homework. I guess it took me longer than most to fathom that people would go so far as to sell fake jeans. I know people are passing off fake Louis Vuitton's all the time, but I can see that there might be a big of a profit there for the dishonest seller. I never knew these jeans were coming out of China for $22.00/pair.
Well, 4 of the 7 pair of jeans that I ordered actually came. By this time, I was well aware of the "fake jean" problem and had gone to HONESTFORUM.com. Here, I read some of the threads that were posted about different people's jeans. Nothing too insightful - I saw a lot of pictures of people's personal jeans they had posted. Then I came across a thread that referenced a website that is actually in German, but can be translated into English without too much of a language barrier. "FAKE OR NOT FAKE" is the name of the website. I don't think I'm suppose to leave a link in this guide, but please feel free to email me if you would like the address. It gives the CUT numbers that are imprinted on the fakes (not the style numbers) and it has not been wrong once. I found the four pair of jeans I actually received were fake just by comparing the cut number to the ones on this website (which is updated regularly). It took me 2 months to get my money back from this company (Luleeta) after they decided to charge me a 20% restocking fee (yes, also on the ones I didn't receive in the first place). The moral of this story is there is no "7 For All Mankind Jean Fairy" out there that is taking a loss on selling designer jeans just to see happy buyers.
Below are some tips I have picked up myself along the way. I am in no way claiming 100% accuracy in these tips, but they have been true for me -
1. If the cut number is not pictured or listed, ask the seller to provide it to you. If the seller does not respond, do not buy the jeans. You won.
2. I don't know when I've gone to Saks and bought a pair of jeans that came in the "original wrapping". Even the pairs I've ordered online from reputable companies (not Luleeta) don't come it the "original wrapping". When a seller post that it comes in a nice original plastic bag with the size strip down the leg, move along, they are probably fake (and I do say probably because I realize I'm not an expert).
3. When you decide on a style you like, check out other reputable websites to see if that style has gone on sale. If so, the pair you are looking at on eBay is more likely to be authentic. The style that came out last week with a MSRP of $995 will more than likely not be available to anyone, anywhere, for less than a 10% discount for at least 6 months. So when you see that stock photo of "$995 NWT 7 FOR ALL MANKIND GREAT CHINA WALL STUDDED WITH DIAMONDS IN A PLATINUM SETTING, SZ. 27" with a starting bid of $59.99, you've either run into that elusive jean fairy who loves to take financial loses, or you're staring at a pair of fakes.
4. If you do purchase jeans, or any item, from a non-eBay website that takes direct Paypal transfers, DO NOT use that option. Always use a credit card. When you transfer money from your Paypal acount to a non-eBay business, you lose all control over that money. With a credit card, you can dispute the charge. Paypal does not back any transactions outside of eBay. If I had known this, I would not have had to give everyone a homemade wreath for Christmas.
5. I know everyone would choose a pair of authentic jeans over a pair of fakes jeans any day, but if you had to pony up some cash to the IRS a couple of weeks ago, and find that you just don't have $180 to spend on jeans, I will be 100% honest and tell you, I love my first pair of fakes... Thank goodness I only paid $45.
Again, what I have written here is only to be used as a reference. I have bought and sold enough on eBay to know that honest sellers make mistakes too.