Damage by guest

Hi Hosts

Hopefully other hosts may be able to share their experiences and thoughts about this.  We had lovely guests staying and I collected a Damages Deposit of CHF300 in cash on arrival.  When I collected the Deposit in person, I explained clearly what it was for and the guest accepted the arrangement.

They caused damage which my insurance has covered.  The question is, is it reasonable for me to withhold the deposit to cover loss of earnings, as I had to close the apartment for 5 nights?

Unfortunately a heavy, sharp edged item was dropped into the toilet bowl, which cracked the bowl right through.  This resulted in pieces of the ceramic falling off, both inside AND outside and a leak.  Basically the toilet was unusable and had to replaced.  A plumber called to inspect the damage within 24 hours, but there was a delay while a new toilet bowl was ordered and installed.

What do you think?  I would like to keep at least some of the deposit to cover the 5 days loss of business and the administration involved.  Generally, I do not charge guests for minor damages, but this is different.

Many thanks in advance.