The current beta is free.
Will is the cost of the final version?
Free avast for Mac will be free for home and non commercial use.
Just so there is no misunderstanding… The current features of the Mac Avast 7 beta app will continue to be offered free of charge?
I’m not trying to be a cheapy here - but I am needing to evaluate my options as I intend to make a purchase decision soon for a Mac anti-virus app and I need to make sure that I understand all of the features and prices of the various software offerings.
Yes. 
Will it be ok to use for business use until a paid version becomes available?
For business use contact your local reseller for a license http://www.avast.com/locate-dealer
A license for the free version? (there isn’t a paid version is there?).
There is not a license file as such, you just need to pay for use in a business environment.