I had similar experience in past..
Here is what I suggest

1. Check what is written on your contract. Does it mention anywhere that such type damages to be fixed by you
2. Doesn't matter if his agency is informed or not. He is at falt there if he has not ionformed the agency and not you
3. It might be the case that agency is not ready to fix the oven becuase of some other reason such payment due from his side etc ...
4. Important is to know if the oven is owned by the agency or did he purchased it himself
5. Irrespective of who owns the oven whether it is covered under insurance or not.
6. Try to reach out Mieterverband in your area they charge you 100 CHF one time registration fee but will guide you properly. I dont know if this agency exist in your area. They might also give you some free advice.
If you visit them then take your contratc copy and any kind of written communication (email etc) you had with him.

7. Last but not least try to talk to him and politely pass the message that you may go to court this might change his mind and you may be able to settle the matter amongst youself. (I had doen the same...)

all the best
cheers

Sublets are legal IF you have a sublet contract from the company doing the initial lease. For example, for legal reasons, my girlfriend sublets (from me) a (commercial) place that I rented (as she never would have been accepted as a tenant due to lack of income).

Tom

Sure, but they can't refuse as long as the conditions aren't abusive. I'm assuming the contract was a normal one. So he might get a letter saying he was a bad boy, but he's not going to get in any sort of trouble.

I could be wrong, but I seem to recall that not paying the deposit money into a properly controlled account is illegal?

or get a good lawyer and buttonhole him ...

...just be careful what you threaten, it could backfire as blackmail or extortion if he has another fit.

I doubt anything more happened than a fuse blew, either because all the appliances plugged in at once exceeded the amp rating of the fuse, or a plug was faulty. In any case, a microwave doesn't cost CHF 850.

Do you at least have a receipt for the deposit? If not, you gotta problem.

I'd suggest you set up a meeting in a neutral place, not the apartment. Go there with some cool-headed person you know who you have fully put in the picture, and try to reach some settlement.