To be honest if the caravan does not have heating already there, a fan heater or small oil filled radiator would do the job and be more cost effective.I.M.O.
------------- It is a wise man who has something to say.
It is a fool who has to say something.
I have a gas blown heating system but mostly use a fan heater. Free on sites where you pay a set price for electric. I feel happier to put it on a low setting over night. I have gas and co2 alarms but still happier with electric over night. Caravans are not hard to heat.
Fred
Amazing family weekend with old steam engines, classic car displays, market stalls, and full catering and bar. And camping on site - Save £25 by booking in advance.