How much more could Lucy bid for the house to keep the IRR nonnegative? A longer explanation: how many dollars you can add to 200,000 so that IRR goes down to zero. Buying costs still apply (e.g. if you bid extra $100, you actually pay extra $105). Keep the selling price the same as in Q17 (i.e. if you bid more, the selling cash flow does not go up). Hint: this question is designed to be done with financial calculator, not with a regular calculator.