It's not clear exactly which years you need. TurboTax is only available for 2015 and later. You cannot use TurboTax Online to file for past years. TurboTax Online is only for the current tax year, which is now 2018. To file for earlier years you have to use the CD or download TurboTax software for the years that you need. You can purchase downloads at the following link. You have to buy each year separately. There is no free filing for past years.
http://turbotax.intuit.com/personal-taxes/past-years-products.jsp
You might get a better price from a reputable online seller that still has TurboTax in stock for the years that you need. If you see someone selling TurboTax for 2014 or earlier, don't buy it. It will not work correctly.
Tax returns for past years cannot be e-filed. You will have to print your past-year tax returns, sign them, and file them by mail.
It's not clear exactly which years you need. TurboTax is only available for 2015 and later. You cannot use TurboTax Online to file for past years. TurboTax Online is only for the current tax year, which is now 2018. To file for earlier years you have to use the CD or download TurboTax software for the years that you need. You can purchase downloads at the following link. You have to buy each year separately. There is no free filing for past years.
http://turbotax.intuit.com/personal-taxes/past-years-products.jsp
You might get a better price from a reputable online seller that still has TurboTax in stock for the years that you need. If you see someone selling TurboTax for 2014 or earlier, don't buy it. It will not work correctly.
Tax returns for past years cannot be e-filed. You will have to print your past-year tax returns, sign them, and file them by mail.
Note: The desktop software you need to prepare each prior year return must be installed/downloaded to a full PC or Mac. It cannot be used on a mobile device.
Also note that your extensions have expired. An extension is only for 6 months. You are now just filing late for all prior years. If you are getting a refund there is no penalty for filing late. However, it's too late to get a refund for 2015 or earlier. You can file the tax return, but if it shows a refund you will not get the refund. If you owe tax for an earlier year, you must file the tax return and pay any tax that you owe. The IRS will then bill you for penalties and interest for filing late and paying late.
"do i need to hire a local tax man? " If you owe for those years then I would strongly recommend it. A tax professional or EA that can represent you before the IRS to get the best deal possible for back taxes and penalties (not a store-front tax mill or TV advertiser).