Towing Weight help!!!!

(Moved to Towcars)

Hi all, we have just joined and are thinking of buying our first van! now, I am by no mean thick but I am struggling a bit with wieghts. I have a 2010 c class merc which shows a braked max towing weight of 1800kgs. Fine I think I can tow a van with a max MTPLM of 1800kgs but when I put in the van I'm looking at (lunar lexon 640L) is put a cross in here! I am an experienced LGV driver and have no issue with pulling or reversing and know about the 85% recommend but is my understanding correct? is 1800 the max weight I can pull with this car? any advice most welcome from confused.com lol