The IRS told me they will give me a payment plan, and I don't need a lawyer. Can't I just handle this on my own?
What they don't tell you is that not everyone qualifies for an installment agreement, and even if you do, crushing penalties and interest continue to accrue on the debt while you pay out the principal and interest.
Most importantly, there are other options available to most taxpayers. You may be able to have penalties abated/forgiven, you may be able to save on your overall liability through the IRS' offer in compromise program, bankruptcy can also clear out personal liabilities if you otherwise qualify for Chapter 7.