Stick a fork in it, it's done.
Well, few finishing touches; maybe some double sided flooring tape to lock down the edges, and of course all the shelving to go in, but that's the structure wrapped and roofed.

Dimensions:
9 meter triangle side
3.8 meters tall
100 square meters of plastic
35 square meter footprint

~100 square meters growing space, depending how you use it.

Total cost:
NZ$120/€68
($95 for the plastic, about $25 for screws, nails, etc. All wood felled or recycled).

Took three of us about 7 days to build, not including getting the materials together, but it would've been about half that if we hadn't been inventing the thing as we went.

Next one will be done slightly differently, bit easier to construct but generally the same. Maybe a third larger...