What can the Koblenz WD-12 C314 pick up?

It is a wet/dry vacuum, so it takes dry debris like sawdust and dirt and also standing water from spills or leaks. Switch the setup between wet and dry use as the job requires.

How big is the tank and how often will I empty it?

The tank holds 12 gallons. That is roughly twice a small 5- or 6-gallon shop vac, so you empty it less often, but it is heavy to carry when full.

Does it need a bag or filter?

Wet/dry vacuums of this type use a filter for dry pickup and typically run without a bag for wet pickup. Check the manual for the filter setup before switching between wet and dry jobs.

Is it good for a home garage?

Yes. The large tank and corded power suit garage floors, workshop dust and car cleanup. Its size is the main drawback if you need to carry it up stairs often.

How does it compare with a smaller shop vac?

It offers more capacity and fewer trips to empty than a 5- or 6-gallon unit, at the cost of weight and bulk. Smaller vacs are easier to move around tight spaces.