I have been looking at alternatives to tent camping - one being a teardrop type camping trailer. I know most of you guys are US based and so 'small tow car' to you guys means something like a Ford Focus or similar 4-cylinder, front wheel drive car, but my tow car is small on another scale! I have a classic Mini Clubman Estate, which is a variant of the original Mini, manufactured from 1970 to 1981. The maximum towing weight for my car is 300kg, or just under 650lb - here it is:

As a result of this, I am particularly interested in the very light-weight builds like Roly's 1/4 Nelson Stacker, mikeschn's ultralight and kennyrayanderson's proposed uber ultra light, and am thinking about building a TD using these as inspiration.
My current thinking is that I would like to build a fully insulated TD using a foam insulated torsion box floor 2" deep with lightweight plywood skins, foam cored sandwich sides with a GRP outer skin colour coded to my tow-car with auto paint, wood framing/reinforcing and thin ply inner skin and a roof made with an aluminium outer skin, foam insulation and a thin ply inner skin.
Profile-wise I like the shape of the Cub/Modernistic, shortened to suit an 8'x4' sheet (10' ply is almost impossible to find in the UK!) - Mike's Ultralight profile looks to be almost exactly what I am looking for.
I am planning to use 10" wheels with the same offset and 4x4" PCD as the Mini - torsion half-axles are easily available in this configuration here and it would mean a spare wheel/tyre is not needed, cutting down on weight even more!
For the chassis I am thinking along the lines of either Angib's superlight chassis or separate 'axle' and 'drawbar (tongue)' as planned for Mike's Ultralight and Kenny's uber-ultra.
All of this depends on me restoring the Mini (5 years of daily use have taken their toll, especially the last 2 winters) and finding a way of integrating a removable towbar into the car, so actual build progress is going to be a way off yet! In the meantime I will be doing lots of research and most likely asking lots of questions to make sure when I start the build I'll be able to get on with it and complete it reasonably quickly!
John.