How many resources are enough?

Question

It seems most planets I come across begin as being "Rich" in resources. And Palladium in particular is extremely abundant. However, probes aren't free and I haven't found an in-game mechanic for translating surplus resources into credits. Fortunately, I'm fairly certain that the number of items to be bought with these resources is finite. (That is, if you ignore the fact that certain ship & crew "upgrades" can be re-purchased infinitely.)

So, I'd like to know how much of each resource is needed to research all available upgrades to their maximum level, and to use each re-spec/re-train upgrade once.

In my case, I'm playing a new copy of Mass Effect 2 on the PS3. This includes the Cerberus Network DLC (which includes several component DLCs) and Lair of the Shadow Broker.

Answer 1

This is taken from the mass effect 2 wiki:

Know that it only takes 195,000 Palladium, 275,000 Platinum, 220,000 Iridium, and 31,000 Element Zero (+5000 for every Bonus training and +2500 for every retraining of powers and skills) to purchase EVERY research project in the game

However, if you count in the rewards for missions and assignments:

Mining isn't the only income for resources. If every mission and assignment is completed, and all resources on the mission are collected, only 166000 Palladium, 243000 Platinum, 191000 Iridium, and 23000 Element Zero (+5000 for every Bonus training and +2500 for every retraining of powers and skills) need to be collected. An additional 50000 less is required in each if a Mass Effect 2 play-through has been completed, meaning that with this bonus there is no need to mine Element Zero.

Thus:

195,000 Palladium, 275,000 Platinum, 220,000 Iridium, and 33,500 Element Zero is needed in total for every project + 1 power / skill retraining.

Taken from here