I think the answer that you can't get the money back may also be wrong. Depending on what the mistakes were, there is a form 3115 that can be used to correct mistakes with depreciation. Since this preparer is already shown to be not competent, you may want a second opinion from someone else. (If you go to court, you will need to hire someone to calculate and testify to the loss in any case.)
But to recover from this accountant for their mistakes, you have to sue them. That's how it all works. A legitimate accountant should have errors and omissions insurance to cover these things, and they might negotiate a settlement, but even then, you usually have to file suit to get the ball rolling.
If they have a professional license like a CPA, you might be able to file a complaint with the licensing body, which might result in a black mark on their record, but probably won't result in financial recovery without suing them.
