Building a cabin under $6000 possible?

[kalakoa]

"deep corrugated", classic tin-roof style but a little deeper.

Also available in clear polycarbonate. For a cheap "skylight", install one clear panel somewhere in the middle of the roof, and switch the overlap so that the clear is under the metal on either side. The sunlight acts as a natural disinfectant against mold/mildew/etc.