There are many items listed on ebay as being "genuine" leather which are only "genuine" pvc. Stick to the following simple rules to avoid being ripped off:
1) If you are buying a leather coat or jacket, be very careful when bidding for anything which is advertised as "Armani", "RGA Armani", "Reportage", "RGA Reportage", "V", "Emporio Armani", unless you really know which is fake and which isn't (somebody else has written a very useful guide on this). Yes, people do list genuine Armani leather jackets, but would they start the listing at 99p? Most of these are PVC Sunday market specials. If someone is selling a real Armani item, it will usually have a price tag to match and some sort of authentication - a certificate or a sophisticated label.
2) Is the jacket the sort of thing you would see at the night club, or the job centre? Even old "designer" leather jackets still have style. Cheap PVC ones look just that - cheap.
3) If the photographs show the inside label, does it say "genuine leather" or is the label "cow hide" shaped? If it doesn't, it is almost certainly PVC.
4) In the photographs, does the jacket look too shiny? You can get shiny "patent" leather, but real leather items (especially used ones) will show a patina (signs of age) and creasing in the right places. PVC doesn't crease so well - after only moderate use it will often split or crack at the stress points. You will probably see some of these "Reportage" jackets listed on the right hand side of this guide (note - these are nothing to do with me! I haven't listed them and definitely do not endorse them!) Look at the pictures to see what I mean.
5) If in doubt, ask the seller if it is real leather with the appropriate label. If they get stroppy, they probably have something to hide. Some sellers are not fully clued up and really think that they are selling a genuine leather garment. If they have made a genuine mistake, they should be grateful that you have saved them from an Ebay complaint!
6) If you receive an item and you are not sure if it is leather, then a) Sniff it. Real leather has a "leathery" smell (obviously!). PVC doesn't. b) Is it heavy for its size (leather), or lightweight (PVC)? c) Look at the reverse side of the leather. Does it look like suede (leather) or is it cloth backed (PVC)?
7) If the item was sold as leather and isn't, you will have a valid claim against the seller through Ebay's protection policy. But be quick - the sooner you act, the better your chances of success.