You do not have to work with an attorney to apply for a tax payment plan with the IRS or state. You can contact the tax agency directly and handle the process on your own. However, because tax laws are so complex and ever-changing, by working with a skilled tax attorney who has in-depth understanding of federal and NYS tax laws, you increase your chances of negotiating a more favorable installment agreement. A tax lawyer is especially beneficial if you owe a large amount of tax debt, have unfiled returns, had an existing installment agreement on which you have defaulted or have a lien against you or are being threatened with a levy.