[hussong]

Berlin resident here. I agree that it's a tough problem to solve and would make verification of hosts (maybe prohibitively) expensive. You'd have to check that the person listing the place is a) actually the tenant, b) is in good standing with the landlord, c) has permission to sublet (without pre-approval of individual subletters by the landlord).

In practice, most Berlin landlords won't ever notice their flat being occasionally sublet to tourists by the tenant, but they will probably not be too happy when they notice.

[slowpoison]

Actually, verification of hosts is not THAT tough and Airbnb already has a solution - "Airbnb verified" photos of the listing. Airbnb offers (in big cities at least) to send a photographer to your address and have him take pictures and upload to your listing page. This verifies to a reasonably decent degree that the person listing the property is the owner too.

[bignoggins]

well in this case the tenant did not pay rent for 4 months, and instead rented it out on airbnb for those months and pocketed the change. If the tenant funneled the airbnb money into rent I'm sure it wouldn't be as big of a deal as it is now.

[hussong]

Sure, in your case, the tenant's move was particulary bold. Owing two months rent to the landlord is grounds for immediate termination of the contract and eviction in Germany btw.