Points To Look Out For -
Craftsmanship - Designer jeans can usually range in price from £70 to anthing up-to and above £400, due to this fact the manfacturers have strict quality control measures and it is highly unlikely that the jeans you will be purchasing will have any flaws. Pay particular attention to design's, buttons and label's as these are the main give aways.
Labels - the label is a very telling factor when looking for fake vs authentic. Although alot of the fakes are getting much closer to the original labels ther are still clear differences and the first thing to look for is the TEXT STYLE and layout as this is the easiest thing to look out for. Some jeans have a holographic strip in the label (i.e True Religion) and this can also be a telling factor but please dont take this for a given becuase alot of styles do not have this.
Branded Plastic Bags - NEVER EVER, EVER buy designer items that come with branded plastic bags as they are almost certainly fakes, manufacturers and retailers do not stock these bags but alot of the counterfeit compaines do and this would immediatly ring alarm bells if the item you where looking at had a branded polythese bag.
Look At Your Seller - Always look at your seller, feeback is a good place to start because if they sell fakes then you can almost certainly say that someone would have commented on their items, Again please do not take this as a given because i recently recieved a negative from a buyer who bought a Gucci wallet from me, They used the buy now option and then immediatly left a negative feedback (Within 5 minutes) turned out to be a 15 year old kid using thier mums account and the feedback was removed but just be aware that this type of thing happens. Also look at their other items and the price they are selling them for. Designer manufacturers do not wholesale to just anybody and there are no buying bulk discounts so 0.01 listings could indicate a problem or items selling without much information or the correct name of the jean.