This achievement will just come over time. There is no need to manipulate saved games and sell all your items. You can make over 1k in credits from the end of the month council meetings alone, not to mention some of the side missions throughout the month (I got mine doing a side mission where I gave India 5 Plasma rifles for 2,100 credits even though by the end of the month, I had all but 5 satellites in orbit and would be getting 1,085 credits). If you're looking to complete this game, don't waste your time headhunting this achievement. You will get it naturally.
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