The smallest of the range are the teardrop caravans or pod caravans as they sometimes are referred to. These are very retro as they come in all sorts of colours and you can apply your own graphics on the side. You can tow some of them even behind a three-wheeler trike. They seem to be a fashion thing at the moment and im not sure of their longevity in terms of holding their value or desirability on the second hand market. However, they are not expensive to start with and will give you a good nights sleep and are easy to store away. They are great for festivals and the younger end of the caravan market.
There are many small independent UK manufacturers in this market but the key one tends to be German manufacturer Tab or T@B caravans. These are probably the most expensive and best built but will hold their value longer as apposed to he UK independent manufacturers.
Most have just simple sleeping with the kitchen being on the outside, so not much fun if it’s raining when cooking your bacon & eggs. You still have to find a tree though if you want to go to the loo or you can purchase a pop up loo tent. They are an alternative option to a small tent but with a solid roof over you. Quirky and fun sums up this range to me.