Don't buy random one-of -everything tools until you know 1) what jobs you really want to do and 2) what your specific bike(s) need. Obviously a good quality set of Allen keys is essential as is a good floor pump and tire levers. Beyond, that buy what you need as you need it.

Eg. don't buy a square taper crank puller if you have a HTII crank, don't buy a Shimano cartridge bottom bracket tool if you have their HTII bottom bracket, etc.