You have neglected it far too long. Either bulldoze it and start over or sell it to someone who will bulldoze it and start over. Unstable ground is extremely costly to stabilize. Extremely! The house isn't in good enough shape to save. Bulldoze it, stabilize the ground, and then build what you want. If you can't afford it, sell it and don't neglect your next place or you might end up with something you cannot sell. You might have that now. Well, you might be able to sell it but, for less than what you have into it.
Certified Paralegal, with 25+ years' experience & with Real Estate law experience.