It really depends on what bikes you plan to work on, particularly if you want to work on older bikes. I have a drawer full of just bottom bracket tools, and a drawer of various freewheel and cassette tools, and a third drawer of just crank pullers (OK, that drawer is smaller than the others). And I do not have every tool for sure. Now if I just worked on modern bikes, I would not need at least half the tools I own.

Best bet is to acquire just the tools you need for your current bike(s), and then add to them as you go. Common tools: a good chain tool, a good cable cutter, a set of cone wrenches, freewheel and cassette tools, crank tool, bottom bracket tool(s), allen wrenches, spoke wrenches, pin spanners, chain whip. How far you go and how much you spend depends on your budget and the amount you plan to work on bikes. And consider USED tools, about 90% of my tools were bought used.