According to article number 8 of the law of 6 July 1989, the subletting of a furnished residence in France is authorized under the following conditions:
There must be prior agreement from the home owner. The rental contract must not have a mention in it forbidding the subletting of said property.
The rental amount stated in the subletting must not exceed that of the amount established in the rental contract.
Ask for written consent from the home owner. In case the conditions are not met, and if the home owner can prove that a subletting took place, he can legally interrupt the subletting agreement.
Yes, MorningCroissant offers an insurance policy for all your sublettings, as long as you have the consent of the home owner. Details can be found in the following link : Insurance & safety. The multi-risk insurance policy covers:
Damages as a result of fire, flooding, etc...
Damages to goods belonging to the home owner