I'm not an Accountant or an Attorney but from what I have read I believe you are going to need one or the other. There are some good Tax Attorneys but I recommend an Accountant. I hope you have good records and have all pertinent information categorized. If your information is not categorized I recommend that be done first. Know was of no help but want to wish you Good Luck.
I have a local inexpensive CPA who is retired and fights for his clients. He has seen me through tough situations. I wish I had hired someone years ago.