Yours tool needs will vary by the age of your bikes. Older bikes need cone wrenches, headset wrenches, and bottom bracket wrenches.

Newer bikes use a lot of allen/hex wrenches.

Either way, you will also need tire levers, a chain breaker, chain whip, and cassette or freewheel removal tool.

I suggest that you buy better quality tools as you need them. Park Tool makes reasonably priced tools that come with a lifetime warranty.

The kits usually include lots of tools that you don't need, and are assembled with collections of tools for fairly recently made bikes. If you have older bikes, a lot of the tools will not work.