In the administration area of Auction Factory you can find the Users list with basic user information and management.

Registration is handled by Joomla and users then have to fill in an Auction profile to use the auctioning system. Until the auction profile is filled, when attempting to access Auction Factory menus, users will be redirected to the profile filling page. For example, when attempting to post an auction.
Viewing an auction does not require a user profile or even logging in.

Here you see user's emails, names, statistics about bids and auctions along with their Status. You can also Block/Unlock allowing you to ban that user from the Joomla Login and automatically from Auction related actions.

Users with Verified and Powerseller ranks can receive differential prices for the payment items. These prices are set in the config of each payment plugin.

Clicking on a username it will take you to the details page of the respective user.
On the details page you can see personal details and statistics related to the user (including custom fields) along with the user balance, messages, ratings and bids.