I have 5 kids, so unexpected costs always come up. To stay on budget, we don't spend any money for a week.

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When my partner and I just finished a massive laundry room remodel that stretched our budget a bit, the worst happened. The contractor was putting the finishing touches on the floorboard. He pulled up a piece of wood and found black mold near the fridge from a leak, and kept finding more and more, down through the floorboards to the basement.