Any fixed asset register can be 'archived' (which will remove it from your subscription).
The easiest way to do this is to go into the Register you want to archive and click on 'Register Settings' in the left hand menu.
On the 'General' tab in Register Settings, you'll see an 'Archive' button at the top right of the screen.
Archiving is reversible, but you'll need to send us a support ticket to recover an archived Register in error.
The above instructions are for deleting a whole fixed asset register. A different process for how to delete assets in AssetAccountant is detailed here.