Multi step process:

1. Buy catnip. Crumble is to release the scent, on THEIR climbing trees, scratching posts, in their beds.

2. At the same time: use a squirt bottle. Mix equal parts, water and white vinegar. This is a mild mix and humans will not smell it. Bats, being down close to it, WILL. Squirt all the edges / corners of the new furniture; the sides and the backs. Start by doing one small area, just to be sure the color won't run (95% of fabrics can take this mix with NO issues).

Repeat the WHOLE THING at regular intervals. Do NOT wait until they start scratching stuff! Mark it on your calendar and DO IT.