I love Auctiva too and welcome to the throng of followers.
By "Domain", do you mean you've purchased an Auctiva registered internet domain for the Auctiva Store? If so, yep, it's real all right. It's absolutely a bonified internet registered domain.....kinda cool isn't it?
Looks good on the stationary and business cards, if you go that far.You can do some limited things with the Store page from the Store tab, including an About Us page for the Store.
Pictures are loaded to Auctiva and they size and store them for you. See the Images tab.
Auctiva doesn't host EMail accounts. I did make the suggestion a few months back, and Jeff the Auctiva CEO responded with a work-around suggestion in the Forum. Here's a link to the thread:
https://community.auctiva.com/eve/forums/a/tpc/f/855609321/m/7621021482
Auctiva now owns Sellathon. I'm hoping there are improvements coming, including better reliability/accuracy on the counters. I've suggested adding a counter to the Store page too.
Hope that helps and have a good one.
Danno