I am an S-Corp with single employee (myself). What is the best Turbo Tax edition to buy to file my company as well as personal taxes (W2 + K-1)?

There is no single TurboTax product that will file both the Form 1120S tax return for your S corp and your personal Form 1040 tax return. You will need two separate products.

To file the Form 1102S return for the S corp you have to use TurboTax Business, which is a different product from TurboTax Home & Business. TurboTax Business is available only as CD or download software that you install on your Windows computer. TurboTax Business cannot file your personal Form 1040 return. You can learn more about TurboTax Business, and purchase it, at the following link.

https://turbotax.intuit.com/small-business-taxes/

For your personal Form 1040 return you can use any edition of the CD or download TurboTax personal software. The personal editions cannot file the Form 1120S return for your S corp. If you use TurboTax Online for your personal return you will have to use the Premier edition or higher to be able to handle the Schedule K-1.