Non Filer

You'll find different opinions on this, and even my advice might be tailored to the client's specific circumstances, such as what the returns would likely show once they're prepared.

However, I would begin with a Form 8821 to enable me to phone the IRS Practitioner Priority line to determine what the IRS shows for this client and what years actually need to be filed. Going back that far, it's likely that the IRS would have lost interest in the older years and/or would have filed SFRs. Also, the IRS would be able to fax to you many of the inputs (a "Wage & Income Transcript") to handle the returns that are still on the table. I definitely would not head off in any direction before knowing what the IRS expects since you'll only have to reconcile things with the IRS expectations sooner or later anyway. The IRS should let you know which returns need to be filed and which ones would be a waste of time at this point.

In lieu of a Form 8821, you can also handle the call to the IRS Practitioner Priority line as a 3-way call with the client. There are mixed opinions on the prudence of doing it this way. I've never had a problem with it, but if you have an excitable or argumentative client, you probably don't want to be part of a 3-way call between him and the IRS.

Once you know which returns are still in play insofar as the IRS is concerned, then you'll know how to proceed.

A strong word of caution. Make sure you get a substantial portion of your fee up front, at least 50%. Clients such as this are quite convincing that they're ready to see these matters through to a conclusion, but they quickly lose interest once they see it's going to cost money and they'll actually be required to pay you and the IRS. That's the best way to sort out whether you're going to be wasting your time. If the client can't or won't pay a substantial portion of your fee up front, then he hasn't really reached the mindset to follow through. Trust me, no money upfront means that ultimately you will have found this client to have been a colossal waste of your time.

Also, when a client stops filing, it's almost always because he determined that he would owe for the year that he began skipping. The client needs to know that the day will come when he'll most likely have to write a check. If he's not willing to accept that outcome, then he's not ready to proceed. 

I tell clients such as this that what they've done is tantamount to not going to see a dentist for several years. When you finally do go, it's not going to be painless and it's not going to be cheap, but you have to do it or live with deteriorating consequences.

All this having been said, I would likely make the call to the IRS PPL at no charge to the client and request the Wage & Income Transcripts for the years still on the table. That shows the client that you can put the wheels in motion with just a phonecall, but it also gives you a good readout of what the returns will involve so you can agree on a fee. Of course, the Wage & Income Transcripts don't tell the whole story of any tax return, but they're an excellent jumping off point.