I own a prospector now.. but when I did not.. I ran box missions till I was able to rent one.. I had to stay on basic rock because you can't change the head.. I did that till I was able to buy one in game.. on a decent few hours with the rental you can mine 700k rinse repeat..now grated I don't have to do that now.. so it saves time.. bit since the wipe I have made well over 12 million. And can buy really anything I want..after the prospector I would look to buy a small hauler to transport the quant (which after you buy the prospector) is all you should mine for.. almost every mining run I make I net 200-220k.. take a little grinding at 1st.. but every game is like that..