I made a small scale solar dehydrator out of
cardboard. It may not be as efficient as one made from wood and properly sealed, but it works.... I haven't tried anything more ambitious than herbs and flowers, so I don't know if it is powerful
enough to dry berries and other fruit. Also, I suspect that fruit would likely stick to the cheesecloth, so I'd have to think up some new trays to use before drying fruit.
Just as a note, I found that the chimney draws better when it is pushed down a bit more than is seen in the pictures.
As you can see from the unpainted pictures, the size is about 2 1/2 feet tall with legs. You can use the tissue boxes for scale to see the size of the rest.