Office 2016 for Mac now available as stand-alone software. I’ve been exposed to Office 2013/Windows, and to get anything done, I have to use Office 2011 on my Mac.
I wouldn’t even install Office 2016 on my Mac for $100 even if it left the old version intact. More likely, though, it clobbers the previous version. In that case, I’d only do it for the cost of a new computer—so I could throw out the old computer with Office 2016 on it.