There are several tools that anyone who may need to do a little bit of self maintenance on their car should have in their garage. While not everyone will able to work on their own vehicles if you find yourself stuck at home because there's something wrong and have a friend who knows a little bit you might find yourself back on the road without a tow truck or a service truck.
Key items that will be useful in a garage will include a hammer, a socket set, a flat tip and a Phillips screwdriver and an adjustable wrench, also known as a crescent wrench. Ideally you would want to have a full set of open ended wrenches, but adjustable wrenches will work as well. In addition you will want a pair of pliers.
These items will not fix every problem that you may encounter, but they will be a good start on minor things. In addition they can be helpful around the house as well if you find you need to hang a picture or tighten a loose bolt. A small tool kit can be used to quickly repair many small issues that you may find on a vehicle.
It is a good idea to have a few supplies available as well such as a lubricant like WD40 and electrical tape. The lubricant will help to free bolts that may be rusty. The electrical tape can be used if you notice a wire that has been exposed in some way.
It does not require a big tool box to do minor adjustments and repairs in your garage. All you really need is just a couple of tools and a little bit of knowledge.