I bought two pleos off ebay successfully
The key things to remember when buying anything off ebay are:
1. Look for photos of the item in hand. If the seller is using stock images and will not provide their own photos of the item be buyer beware.
2. Ask lots of questions! If the seller will not take the time to answer any questions you may have about the items condition i'd skip that auction.
3. Examine the photos very carefully. Look for any damage not mentioned in the sellers description. If the seller has only one photo or has many photos all taken from the exact same angle ask if they can take any photos showcasing the entire product. Some dishonest sellers may try to hide damage with creative camera angles or will only take photos of an items 'good' side. This is especially relevant when shopping for pleos who are prone to skin damage.
4. Check the return policy. Alot of pleo auctions seem to be "No returns accepted" on ebay so make sure you really want that particular pleo and have really studies the photos and description before placing your bid.
And finally. Remember batteries can always be replaced. Both my pleos came with bad batteries but once I was able to order a new one they ran perfectly. A bad battery isn't the end of the world but you should always factor in the cost of one