Hi,
You can use your own Auctiva account or other hosting services like Photobucket for your images.
You can embed flash type elements in templates. However, you'll need to locate a site to host the flash file, i.e. eBay and Auctiva don't host those files other than the ones they use for their services, like the Auctiva Scrolling Gallery. Photobucket (Pro) and Hotlinkfiles.com are possible alternatives.
Danno