Hi there,
According to Swiss law, caravans which are registered for use on public roads and carry license plates are covered by the compulsory third-party liability insurance of the vehicle which is used to tow them. This means that you do not need to get separate liability insurance for the caravan.
Damages to the caravan by the elements can be covered by a separate comprehensive insurance policy and damages resulting from accidents for which you are at fault can be covered by separate collision insurance. Typically, insurance providers charge just one deductible in the event that both the car and caravan are damaged in the same collision.
Some Swiss insurance providers (Helvetia, for example) offer temporary "vacation" insurance for caravans. If you only expect to use the caravan for few weeks, this can provide a cheaper alternative to getting a regular comprehensive or collision insurance policy - which typically have minimum terms of 1 year.
In your case, however, getting collision and comprehensive insurance is most likely not worth it because you are looking to get a cheap, used caravan with little value.
If you have household insurance, your policy may cover the caravan if and when you end up parking and deregistering it (at a permanent campsite or in your garden, for example).
Best regards from Moneyguru
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