Somewhere inside the Manual it's stated that "overpaying" anything results in the overpayd amout to be discarded.

In account to that, how does the Leadership secondary ability work?

Examples:

1: Buy 1 command counter for 4 (discard 1 influence) then 1 command counter for 6 (and discard 3 influence as overpay)

2: Buy 3 command counters for 10 (4+6, and discard the remaining 1 influence.)

By rules written my gameing group came to the conclusion that °1° would be right, tho reading a few PBEMs i see that "2" is played quite often.

So now i'm searching for the justification, if there is another than "houserules".

I have checked the FAQ.pdf too, to no avail, but maybe i just missed a section in the manual or interpreted something wrong?

Clearign up those typos so it becoems readable..

For starters, you're probably talking about the Logistics secondary, since you quote a cost of 3 for each CC.

Also, when buying several things at once you total the costs and then pay the total, which gives you option 2 - the way most of us play it.

Try to apply option 1 to buying units, for example, to see how painful that would be...

Yes, it's the Leadership card, and the #2 option is correct.