While the drain connection for a garbage disposal is nearly universal and fits standard sink drain holes of 3 1/2 to 4 inches, the size of the disposal unit itself is not. You must have enough space in the cabinet underneath your sink to accommodate the disposal's housing. A larger model may not fit in a compact cabinet or if the existing plumbing is arranged in an unusual way. Before buying a new garbage disposal, measure the available space under your sink. If you are replacing an old unit, it's often easiest to choose a new model of a similar size.

In some cases, it’s more cost-effective in the long run to replace a garbage disposal, but it depends on the specific issue you’re having and the age of your disposal. You should ask a garbage disposal repair tech for a quote to repair your appliance and then see if it would be more worthwhile to replace it. Additionally, garbage disposals last for around 15 years, so if you know your appliance is reaching that age, it’s likely better to pay for a new garbage disposal rather than sink money into repairs.

Most garbage disposals have a reset button that can be triggered with a tool as simple and accessible as your index finger. That said, if you need to perform a more in-depth troubleshooting step, like manually moving the arms inside the unit or rotating the impeller plate, a hex wrench is the most common tool you’ll need. Most garbage disposals come with a hex wrench.

Soil is just one of the items you shouldn't put down a garbage disposal. Garbage disposals are only meant for soft, non-fibrous foods. Large amounts of topsoil, dirt, or rocks will damage the blades of your garbage disposal or clog the pipes. If a small amount of dirt goes down the drain as you repot a plant, you shouldn't have to worry, but never dump a whole pot of soil in the sink for fast disposal.