Leaking roof vent

The last thing that anyone wants to find is damage to their home, trust me, I know. The men that built my parents' house were low bid contractors on a government contract after a fire did major damage to the area years ago and a disaster was declared. We were among the the lucky that got help rebuilding, but that came with some drawbacks.

Being a government assisted building project, it went to the lowest bidder. That left us with a house filled with construction flaws. The foundation had a large crack near the front door, the living room had a crack that went the entire length of the ceiling and turned to head for the front door where the living room went toward the hallway, the kitchen counters were pulled out from the wall behind them, and it was impossible to put up corner shelves because you could not find an actually squared corner in the house.

The worse I think, aside from the major structural cracks, was the improperly sealed fan in the kitchen that caused water to leak into the house during thaw or heavy rains. There are clear signs of leaking on the walls in both the kitchen and the bathroom where they share the wall with the faulty kitchen fan vent. The walls have been painted, but the damage is still there and even after the State sent someone that was supposed to have repaired the vent last year it still leaks.

If I save the house, I am going to need to get upstairs and see what the attic looks like where the water has made its way into the house all these years. I'm a bit scared to see what that is going to be like, even though the guy from the state assured me that there was no damage. He had also assured me he had fixed the leak.