You get the factory tool kit, then your own tool kit. You start at the front of the bike and work backwards. Every time you find you have to get a tool from your own kit, put it to one side. At the end of the exercise, buy new tools to replace the ones you put to one side.
Simples
It also depends on how you're going to carry them. If you can carry a tool roll or similar, you can replace the stamped metal 'spanners' with real ones.