I need to know about pricing on returns for multiple years, and if this really what I need.

[DoninGA]

Without knowing what you need, here is the TurboTax website for prior tax years (2014 thru 2016) where you can purchase a download for each tax year - https://turbotax.intuit.com/personal-taxes/past-years-products/

Prior year tax returns can only be printed and mailed, they cannot be e-filed.

TurboTax software can also be purchased from a reputable online retailer, such as Amazon.  TurboTax does not support tax years prior to 2014.

The TurboTax desktop CD/Download editions for 2017 are on this website - https://turbotax.intuit.com/personal-taxes/cd-download/

[VolvoGirl]

You have to buy each year separately.  They only sell and support the last 3 years back to 2014 now.  Or if you have a simple return you can get the blank forms from the IRS and fill them out by  hand for free.  If you can't find them I have a list of them for all years.

You will have to mail in your return.  And if you are doing more than 1 year, send each year in a separate envelope. Sometimes the IRS will just staple all the sheets together and miss a second return.  Or you might want to go to an accountant or EA enrolled agent in person to help get you caught up.

But what is the rest of your question?  Why do you need to do multiple years?  Did you have income you didn't report?  Or do you need to amend a prior year?