I posted this a while back in another tool thread. How many tools needed depends on the variety of bikes that need service, and the depth of service needed. I could probably run a small shop with the tools in my collection. I maintain all of my family’s bikes (more than ten), neighbor’s bikes, and I refurbish kid’s bikes for a local non-profit.
The arrow ( → ) In the list below is my opinion of increasing quality. It also generally denotes increasing price. The list is somewhat USA centric on the lower end, as I don’t have a ton of experience with XLC, Cyclus, etc. The list is intended to be a resource for buying tools one-at-a-time and making decisions on cost vs quality across the spectrum. Whether fixing bikes is intended to be an enjoyable hobby or a source of income, having good tools will make the work more enjoyable and more efficient. While I agree that you can make do without a work stand, bench vise, and other various shop tools, having these greatly increases efficiency and decreases frustration.
I agree with others that you should buy the best hex keys that you can afford because these will be by far the most used tools.
Hex keys:
Pedro’s → Park → Bondhus → Wera, PB Swiss, Wiha, Beta
Cable Cutters:
Pedro’s → Park → Knipex, Felco
Tire Irons:
Park → My own hands → Pedro’s → Schwalbe
General Bike Specific tools:
Birzman, Ice toolz → Feedback → Pedro’s → Park → Hozan, Var → EVT, Abbey
Ratchets, Wrenches, Sockets: Too many to list, but in general:
China → Taiwan → USA, Germany
Pliers:
Harbor Freight, Walmart → Crescent, Irwin, Channel Lock → Klein → Knipex