Personally, if I were doing this, and I might still, I would focus on the challenges of actually mining. The reason is that rockets and probes etc are pretty well plowed areas but while Curiosity, the mars rover, can drill a small hole and using non-replacable reagents look for certain compounds, these things will need to process tons of material from an asteroid to try and extract kilograms of materials. That is a very unsolved problem and a very under funded one.

A lot of current extraction techniques use liquid water (not available on an asteroid), all extraction techniques depend on the raw ore being transportable by buckets or belts with gravity keeping things in place (also not available on asteroids). And many refinement techniques are very energy expensive (challenging to ship to an asteroid). So if you can figure out how to solve even one of those problems and asteroid mining company that hires you will be ahead of the game.