Hi Jo,
What caravan do you have?
I know of plenty Eriba owners who tow a Puck L or Familia (750kg - max 900kg) with a Peugeot Partner / Citroen Berlingo - that's about a 65% match, and one Eriba Puck owner who tows with a Toyota Yaris.
Your Peugeot 206 (about 1100kg ??) should be around a 70% match with your van - should be fine - and the 90bhp diesel engine should have no real trouble even in hilly areas.
Robert