Hello and welcome to the forum.
You are not supplying enough information to make an informed opinion. For example:
Which engine does your car have?
Is it a manual box or an automatic?
Do you know what the maximum towing limit of your car is? (Check the handbook)
What model caravan are you towing?
Have you towed for many years, or is this all new to you?
It's worth noting the 85% tow weight rule is not a law, it is a guide and a recommendation for drivers new to towing. There is nothing to stop you towing at 100% kerb weight.
Towing trailers, caravans and horseboxes with a car, including the weight and size limits, and what licence you need to have
I would personally want to have a tow car that was "on top" of the job as many campsites/grounds are in difficult to get to places and some on difficult terrain (don't ask how I know this!). I have towed everything from a 5cwt trailer to a 40 foot artic box van and being on the limit is a totally frustrating and sometimes scary experience, once you get in difficult circumstances.