The rules on Kickstarter state:
Boosts may be played at any time during the game (unless they specify a phase, in which case they may be played any time during that phase).
The text on the "Bad Reputation" card states:
Discard a card. If you do, gain 30 credits.
Lastly, the rules for the Requisition Phase read like this:
At the start of this phase, after completing the actions on any cards in play with [REQUISITION] icons, each player reveals their hand and totals the value of the Credits on their cards. Then, each player may purchase cards equal to this value. For example, if a player has 70 credits, then they could purchase one card with a Price of 70, or seven cards which each have a Price of 10, or any other combination. However, even if additional cards are added to or removed from a player’s hand after the start of the Requisition phase, that player’s available credits for the phase do not change.
So, at the start of the Req. Phase, I reveal my hand, which includes the "Bad Reputation" card. Let's say I have a total of 70 credits. Since I can play "Bad Reputation" at any point during the Req. Phase, I would assume that after it's been determined that I have 70 credits, I would then discard one of the cards which gave me the 70 credits and my credit total would not be reduced because "even if additional cards are added to or removed from a player's hand after the start of..." the total isn't changed. So I'd have 70 credits even though the total of cards in my hands is no longer 70, then I'd add the 30 credits from "Bad Reputation" to make my total for that round 100 credits.
Did I do that correctly?