Finding the right Caravan

Hi Everyone and I am very sorry if this sort of question has been covered already but I need to get some assistance in finding a caravan match to my car.

Now I drive a Toyota Avensis 1.8 VVTI, Manual hatch back car, now I have been told that the maximum towing weight is 1300 KG. I would be new to towing so I have been advised to go to no more than 80% of that figure. I have been told that the figure I am looking for on the van is the MRO to go by, others say its the MTPLM figure I need to be looking at.

Now I am so confused I dont know what to look at or what I can safely tow with this vehicle, to give you and idea I am looking for something with four births.. Can anyone offer some help or maybe some recommendations of caravans (New) that I can lok at to get a better idea of what I am looking for..

Thanks in advance :)