There's 6 specific things you need to check in the house before you can continue the story, it's not tied to the "when money is involved." dialogue and can be done in any order.
They are:
- The note on the kitchen counter.
- The medicine bottle on the master bedroom.
- Enter the bedroom with the pink cat poster.
- Examine the paper on the 3rd bedroom's desk.
- The computer in the study. (after unlocking the password.)
- The picture frames in the study's wall.
If you still can't continue the story after examining them then I'm afraid the error is from RPGmaker's side and I don't know how to fix it, really sorry about that.