I have a mac and turbo tax does not support that. What is the least expensive option since online is saying $550 and i can get a CPA for less than that.

I assume you need the Business program?   Sorry the Desktop program for $190  is only available for Windows and not Mac.  Can you find a Windows computer you can use like a family or friend?   Otherwise there is the Online version starting at $209.  Which were  you looking at for $550?   

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

Your post is not clear.   What is it that your Mac cannot support?  Are you referring to TurboTax Business which requires Windows?  And you do not want to pay for online TT Business?   

Some Mac users get a Windows emulator program called Parallels so that they can use the desktop download TurboTax Business.  We do not know what the cost of that program would be.

See this website for the minimum system requirements (Windows and Mac) for the TurboTax desktop software -https://turbotax.intuit.com/personal-taxes/cd-download/tta-system-requirements/

What exactly are you needing to enter on a tax return?  The price for the online editions depends on your requirements.  

You can use the Free edition at no charge for simple tax returns - https://turbotax.intuit.com/personal-taxes/online/free-edition.jsp

You can use the Deluxe edition for more complex returns, but not for investment, rental/royalties or self-employment - https://turbotax.intuit.com/personal-taxes/online/deluxe.jsp

You can use the Premium edition for complex returns that can include rentals/royalties, investment sales or self-employment - https://turbotax.intuit.com/personal-taxes/online/premium/

There are also options which have you speaking with a Tax Expert Live which costs more and there are options where you can have your tax return prepared by CPA's or EA's for Live Full Service - https://turbotax.intuit.com/personal-taxes/online/#live