Are we talking about an error on the closing statement? (Often called the HUD or the HUD-1). If so, you might want to start by contacting whomever made the error on the HUD.
Depending on the circumstances, here in New York State the title company, the real estate firm, or an attorney could be responsible for an error on the HUD.
This may or may not be relevant, but just so you know, one function of title insurance is to pay for mistakes that happen connected to a closing. I know of title companies making good--that is, paying real money--on a variety of problems that were not discovered until after the closing.
If the sum of money is large enough, it might well be worth making a few phone calls to see if you can obtain reimbursement fairly easily and quickly. If the sum is very large, a good real estate attorney might be worth bringing on board.
Best of luck to you!
Licensed Real Estate Salesperson
Charles Rutenberg Realty, LLC
127 East 56th Street, 4th Floor
New York, NY 10022
(212) 688-1000 ext. 383
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