We had similar issues. And yes, the Airbnb security deposit procedure is a complete disaster.
We took over this listing from he previous owners last year. At that time there was a much smaller jacuzzi, and Airbnb guests managed to break multiple jets. This was still solved via the previous owners.
We invested in a decent American HotSpring. We had an engineer check the entire jacuzzi.
Two weeks later we had the first issue, as guests clogged the filter with massage oil and they we're even washing their hairs in it. Damage 250 euro's for new filters. No response from Airbnb.
Two months later, Airbnb guests were capable of tearing up the cover. We did get a response from Airbnb, but they didn't want to pay for the full amount of damage: 810 euro.
Now we had a group where they broke the filter lid, a replacement part costs over 400 USD, excluding shipping and taxes. But also the water was so much polluted, you could not even see the bottom, that we had to drain it twice (and reheat, disinfect etc). Total damage nearly 750 euro.
Our house rules state that people will loose the deposit in such cases, but Airbnb wants a full breakdown. And that's hilarious. The amount of time that we spent communicating with Airbnb is way out of line... Probably over 10 hours already, and we're not even there yet.
Their statement: maybe you can glue it! Of course we're not going to replace an entire jacuzzi, but imagine the next guests sits on the lid and it breaks again, causing injury. Then I'm liable. Or the next guests break it again and say 'it was already repaired before'.
Most frustrating: they also don't seem to care about rentals in the meantime. How do I explain a broken cover to our next guests? Does Airbnb really want to have listings where it's acceptable to find tape around broken items?
We're not making margin on deposits! However it's a good measure to prevent party people from trashing your place. Getting damages reimbursed from Airbnb is so painful and slow, that we're considering to stop being listed on Airbnb.
Including other damages in the house, damages now 'eat' up to 10% of the revenue. And the only method that works, A DEPOSIT, is crippled by Airbnb.