It is not the weight that screws you up it is how it is towed what speed etc.
What is the max weight you can tow - see handbook.
Also see what your towing bracket is rated at, see also is it a braked or unbraked trailer, see also what speed are my tyres rated for, see also what are the road/ off road conditions, see also how far are you travelling, see also what is the ambient temp, see also is it high or low sided etc. etc.
Basically the caravanning fraternity recommend no more than 85% of the kerbweight for beginners rising to 100% for experienced people, but there are many factors. If you have an accident (and survive) the plod can do you for having an unsafe load for just about anything :sly
I have been towing caravans for over 25 years (17 with a Terrano) and never had a problem until this year. I stupidly
traded in my 2.7 TDi (12 years from New) for shiny 3 year old Rav 4. Joining the M3 from the west I suddenly felt the back end move and looking in my mirrors I saw the caravan broadside on and swinging form side to side
(missus shouting STOP IT ROBERT). I gently eased off the speed and gently steered to keep myself relatively straight, luckily, loosing energy the swing stabilised. My brother in law, towing behind me, reckoned I was using all 3 lanes and I was going to crash.
Anyway long story short, tow what you can convince a policeman that it is safe and even then take care (Don't use a Rav):doh