214 Research Probe G4
215 Booster Probe G1
221 Research Probe G4
222 Duplicator Probe
318 Research Probe G6
315 Duplicator Probe
317 Duplicator Probe
319 Research Probe G1
313 Research Probe G1
414 Research Probe G2
505 Research Probe G2
508 Research Probe G1
509 Booster Probe G2
513 Research Probe G4
Source: a sticky from GameFAQs.
You should look for some Sightseeing points, too, especially in Oblivia, can give significant boosts to your revenue. https://www.youtube.com/watch?v=e1gHJbCc_xE
My bet with The_Liquid_Laser: I think the Switch won't surpass the PS2 as the best selling system of all time. If it does, I'll play a game of a list that The_Liquid_Laser will provide, I will have to play it for 50 hours or complete it, whatever comes first.
