smugmug
Smugmug is basically a webhost offering us photographers an easy way to create websites (with templates) and sell images from said websites. The selling process (collecting the money, sending out the printed images, ordering the images from a vendor of our choice...) is completely in the hands of Smugmug. Their own privacy policy is found here: https://www.smugmug.com/about/privacy
I can get see the shipping and billing address of the person ordering a print but I cannot delete that information myself.
I can add users to my website to give them private access by inviting them and will then get their emails as user names so that I can allow these specific persons access to specific galleries. These rights I am able to revoke.
There is a visitor tracking feature available, but I as the website owner cannot see from which IP the visitor came, I can only see which galleries/images have been visited in a given time frame and how often they have been visited.
Guestbooks and comments are possible, but demand login via google or facebook. I can see the name of who has made the comment, but as far as I can see I don't get their login information.
Hope this helps you adding smugmug to your list of services, which would indeed be incredible helpful :)