All units/buildings upgrades in terran campaign

Is it possible to buy all upgrades for every unit and building in terran campaign, plus hire all mercenaries?
I’ve been reading some threads about redoing completed mission for zerg/protos research points. However these are old threads, I’ve done one mission and didn’t receive additional points. Looks like it was fixed.

Only if you do the exploit for infinite credits.

What exploit? I tried one with researches, but after completing mission for second time I didn’t get any additional research points. I’ve read this was fixed.

The last mission of the colonists quest-line has you choosing between saving them (and the Zerg viruses they’re carrying) or siding with the Protoss (the correct choice).

If you pick the Protoss option you get paid the credits then you can reload the save before the mission starts and choose the Protoss choice again and you will keep the credits every time.

Cool, I will try that out just for fun. I’ve already done campaign two times, and this time it’s just to get everything if possible.