Just to keep you fully informed, you need to know the disadvantages of used gear. It might come as a surprise to learn that older paraglider canopies are limited to a useful life of only several hundred hours of exposure to the sun.
In some cases, just 300 accumulated hours of exposure to the UV (Ultraviolet) radiation of the sun is the limit. A rough indication of this is flying time, so that's something you need to query, if the seller hasn't stated it.
The material of the canopy and the lines of used paragliders are also damaged by moisture and abrasion. These factors can vary a lot, depending on how careful the previous owner has been. Look for evidence that the lines may have been trodden on.
Another issue with the canopy material is porosity. That is, how easily air can actually pass the fabric. Too much porosity is a bad thing for performance, and can actually become a problem before the color of the wing material has started to fade. To check this requires special equipment, you can't tell by looking at it.
Other issues which a casual inspection won't reveal are shrinkage or stretching of the lines. Some used paragliders may even have lines with broken cores, which means considerably less tensile strength. Yikes! You wouldn't want to be hanging under them in a bumpy thermal at 2000 meters (6000 feet) would you!
If you are silly enough to buy a really old and cheap paraglider, it may have dangerous design flaws. It could be useless, dangerous, frustrating to launch or all of the above. It could be... the Paraglider Canopy from Hell. So be careful when choosing used paragliding gear! Try to arrange an inspection of the gear before you buy.