Used tire sales have a number of associated safety concerns. Tires can only be retreaded a certain number of times. Tire specialists that work at used dealers have to first assess whether any given tire can be returned to service.
Unsafe tires should be sold as scrap tires. They can be used whole as planters or barriers or cut up into rubber pieces that are sometimes used as playground flooring. Storing tires in a warehouse or yard also has safety issues. Tires are flammable and tend to burn very slowly, with fires sometimes lasting for weeks, months, or even years. For this reason, dealers, especially those who handle wholesale and bulk quantities, need to submit a fire safety plan.
Some dealers sell all kinds of used tires. Others specialize. The largest quantity come from cars, but motorcycles and commercial vehicles such as trucks and vans are also important. Off road tires are very specific. Dealers may specialize in any of these. They may work with auto dealers in both buying and selling tires and in swapping worn tires for retreads.
Manufacturers may also deal in used tires of their own brand. The company or may not distribute them through the same channels as new stock.
Dealers may also sell wheels and rims, including custom designs that may be for appearance or to match the other wheels of a vintage vehicle. Antique tires are sometimes bought and sold for this reason. Commonly, dealers buy from garages and from used auto salesmen. They often buy them in bulk.
Used tires are cheap, and buyers have to be careful. A reputable dealer will ensure that they do not sell unsafe goods, and make sure that dangerous tactics such as mixing radial and cross ply treads do not happen.