Markups in Adobe DC Reader, and can you permanently display markup toolbar in reader?

I have a client that has a few people needing to do markups (I guess he means comments)?,  and wants to know if he can use Adobe DC Reader.  It looks to me like you can, but can someone confirm, and secondly, does it allow you to save the Markups/comments tool bar on the default screen at startup?  It doesnt appear to allow you to.  Are there limits to markups with DC Reader on PDF CAD drawings VS Adobe Standard?

Thanks!!!!!