Thinking about doing my gears myself. Advice?

I do most of my own work in the garage. But I don’t have the tools, and frankly don’t want to spend the money on them to only use once or twice. My suggestion would be to have a good reputable shop do the work. Especially if you have never done them yourself.
 
My rule of thumb about any DIY job is:
-Do I have all the tools for the job? If no, what is the cost and likely repeat use of them?
-Do C grade shade tree mechanics like me do this kind of job?
-Will the knowledge I gain help with trail repairs if needed?