Essential Habitation Equipment

Hi all

Does anyone have a rough total weight for the above - the caravan I'm getting (my first) has an unladen weight of 1385kg and a total weight of 1595kg - 210kg. How much of this should I allow for battery, gas, water etc? I've come up with a figure of around 135kgs free for awning, clothes, gadgets etc after this is taken into account - does this sound about right or am I way off the mark either way?

Regards