You may view and download photos from the Listing Media page. Clicking on the magnifying glass icon on a photo will enlarge it for viewing, and you'll see a green "download" icon in the upper right-hand corner of the photo. Click this icon to download a single photo.
By selecting multiple photos on the page itself (by clicking in the upper left-hand corner of the photos, on the empty circle), a toolbar will appear at the bottom of the page with additional options for managing all of the photos. Use the "Download All" link that appears in the green command bar to download all of the photos selected in a .zip file to your PC.