If you have a claim against you by the IRS then the first thing you should do is find a competent tax attorney to handle your case. If you are seeking an Arizona tax attorney or a Phoenix tax attorney these are the things you should look out for when making your choice.
Ensure that the person you choose has demonstrable experience of dealing with IRS matters; if possible try to find someone who has previously worked for the IRS.
Make sure that the attorney is properly qualified with a Masters of Law in Taxation (also known as an LLM). Tax law is a complex area that requires constant study to remain up to date. You should never hire anyone that does not have this qualification and you should also check whether they undertake ongoing studies to make sure they are up to date with changes to tax law.
It’s preferable to find a legal representative who specializes in the area of tax law for the same reason. If possible try to find a person who has had previous experience in the area that your matter is concerned.
Finally you should make sure that your attorney is personable and someone you feel comfortable with and with whom you can communicate. In many cases the resolution of a tax matter can come down to effective people skills and professionalism.