from the caption under the house door/garage images:

Hang it in the shed or make it into a great porch light, you can clip on a hanging basket or anything weighing about 20lbs.

So that's ~2x your estimate, which doesn't seem impossible.

I do wonder what they're suggesting using for the ballast though, that avoids excessive bulk. Another consideration is going to be finding a suitable mounting point in a typical shack/slum type dwelling.