The first and most important step in choosing a used compactor is determining how you intend to use the unit. Many varieties of compactors exist to suit countless applications, and choosing the wrong compactor for the job can mean wasting your money and losing time in the compacting process. Determine if you need a fine particulate matter compactor of the sort commonly used on construction sites, or if you need a fixed compactor used to compress metals, plastics, or other solids. This will help you narrow down your search for a used compactor.
If you will be compacting a specific material only, try to find a used compactor designed specifically for this material. Tire compactors, for example, are designed specifically to compress rubber tires into a bale for storage or transport. Other compactors are designed to handle many types of materials: the compactor might be able to compress metal, plastic, and even cardboard. Some trash compactors can compress any variety of materials placed in the trash bin for storage before disposal. Other types of compactors are handheld units often used in construction settings to help settle soil or other materials before paving or other processes.
Regardless of the type of used compactor you will be choosing, make sure to test out the unit to ensure it starts up and works properly. Look for overt signs of neglect or damage, such as dents, significant amounts of rust, broken components, or parts that do not move freely. Power the unit on and take note of how long it takes to get started; listen for any unusual noises, and take note of any burning odors. While these actions will help you avoid obviously damaged units, they may not necessarily prevent you from buying a unit that will break down in the near future, so it is best to consider repairs or maintenance in your budget before purchase.
Try to find a used compactor from a reputable and well known manufacturer. This is beneficial because you will be more likely to find replacement parts readily when necessary. The manufacturer's warranty probably won't apply to a used compactor unit, but you will be able to get owner's manuals, replacement parts, and even professional guidance from the manufacturer. This does not necessarily mean you should totally avoid off brands, but keep in mind that parts may be more difficult to come by, and quality may not be as high with some of these companies.