Thanks for the link Junkboy. It's a nice design but i have been informed that that trailer is not good enough
The trailer is for the GF and it MUST have a rear galley, MUST have cupboards and shelfs inside and MUst sleep 2.
I took her camping a couple of weeks back in my van and it was her first time not in a tent, she insisted on getting her own van but when i mentioned the yearly costs and tests and taxes that idea went out the window and i finally talked her into a teardrop. My van and my car will pull one no problem but she wants to be able to pull it with her little toy car. I ran the numbers and the max it can pull is 750kg or 1653 pounds so i'm hoping to come well under that maybe 550kg or 1200 (ish) pounds. you really should have seen the amount of stuff she packed for a 3 day camp in my van

.... Plus she will be dragging along a 7 year old so add in all the necessary toys he NEEDS to stay happy. I've been looking at some of the models online and a big trailer like the 10ft Raindrop is 1400 pounds so i'm guessing my creation won't be anywhere near as heavy.
I think I've settled on 6mm (1/4 inch) ply inside and out with 1 or maybe 2 inch foam sandwiched in the middle. I can't seem to find 1" aeroboard locally anywhere any more so i might be forced to go with the 2" xtratherm foil lined stuff..but i think that's over kill on a small trailer. Designs have been drawn up but are subject to change at a moments notice...I.E. the moment she changes her mind.