Mini excavators offer virtually identical features and options to their larger cousins: the only real difference between mini and full-size excavators is scale. Here are some of the features you should evaluate.
Tracks. Both steel and rubber tracks are popular on mini excavators. Steel tracks are more durable and provide good traction on loose dirt.
However, on pavement or landscaped areas, rubber tracks do a much better job at reducing surface damage: a rubber-tracked mini excavator can drive right over a curb without crushing it.
Bolt-on rubber pads that operators can affix to steel treads offer a reasonable compromise. This gives you the strength of steel tracks but lets you switch to the less-damaging rubber pads when needed.
Attachments. Switching between multiple attachments lets you get much more use out of your mini excavator. Different sizes and styles of buckets are used for different types of digging. Other common attachments include augers (for boring holes), thumbs (for pinching or gripping) and hydraulic hammers Some mini excavators even use the same "quick attach" couplers as skid steer loaders, allowing you to share attachments between the two. (For more information on Skid Steer Loaders, read our buyer's guide.)
Many compact excavators offer boom offset or swing booms. This popular feature moves the entire digging arm left or right of center. This allows the excavator to dig a trench parallel to its own tracks, and to do so in tight quarters next to existing walls or structures.
Zero tail swing. Compact excavators with zero tail swing (sometimes called "compact radius" excavators) can rotate their cabs completely within the width of their tracks, preventing the operator from ever bumping anything with the "tail" or back part of the cab.
Backfill blade. Many come standard with a backfill or bulldozer blade that attaches below the boom, making it easy to refill and level after you're done digging without having to change attachments.
Enclosed cabs. As with skid steer loaders, enclosed cabs that shelter operators from the elements are becoming much more popular on mini excavators than they used to be. These often include heat and air conditioning, and can go a long way towards keeping operators comfortable and working at their best.
Anti-vandalism features. If you'll be leaving your excavator at job sites overnight, look for compact excavators that allow you to lock up the controls to prevent troublemakers from damaging the machine or your work.
Unlike some other types of compact equipment, mini excavators are almost exclusively available with diesel engines. (Electric mini excavators do exist, but they're very rare.) A single tank of diesel fuel should give you a day to a day and a half's use.