Quick Tips for Prestiged Mine Potential
Upgrade costs remain the same across all prestiges, the difference is that the rates for the mine raise by more power level. But you also get less SC per breakthrough (which is why there is the recommendation to only prestige one mine per continent until you’ve maxed that mind in P6).
Before you prestige, if you will be practicing your work mine, you want to save up enough cash to cover the prestige and what you’ve spent upgrading the mine so far.
In the game menu, there’s a statistics screen. The net worth listed is the total of that continent’s cash that you’ve earned. If you subtract what you currently have on hand, you’ll find what you’ve spent of that continent’s cash (which could have been spent on mine upgrades, research point purchases, mainland unlocks and a few other things for certain continents).
You’ll also want to note the levels of elevator, warehouse, your work shaft, and maybe some other shafts as well. If you spend the cash differently after the prestige, you could set yourself back.