All mechanics have their tools of choice, and while those choices often vary, there are some tools that all mechanics can’t do without.
Sockets
Many mechanics like to designate a drawer solely for sockets, and for good reason. Sockets are almost universally used by mechanics. The impact, deep-wall, short-wall, 12-point, 6-point, hex and Allen, metric, and standard sockets of all sizes are some examples of these widely used tools. High-quality sockets are a lifetime investment.
Wire Brushes & Wire Wheels
If you live in a particularly rugged environment, one where the vehicles you work on pick up a lot of dirt and mud, you might as well buy a whole bunch of the cheap wire brushes to get through all of that debris, so you can actually get to the mechanical work that needs to be done.
This is why wire brushes and wire wheels are so useful. Wire brushes are sold for specific applications, and good brushes feature wires that won’t come off as easy as the cheap ones.