While I disagree with the prior answer about going to a tax attorney (unless you are going to court or have non-tax legal problems connected with this), I agree that you should go to a good tax professional this year.
File an extension, pay what you think you should owe (and go high, if there is any question) and schedule an appointment in May with a good tax professional that is experienced with 1031 Exchanges and with the possibility of correcting depreciation mistakes.
