i just bought a few $8 and $6 dollar windsheild shades yesterday
the $8 is long enough to cover from the front of the rear door all the way to the back with slack
i am covering all the windows using suction cups for $40
so $39 seems way too steep just to cover the sunroof
DOODELEMENT's sunshade at $39 may seem steep for others but for me it is not.
The shade is professionally assembled. The materials are lightweight, sturdy and perform very well in regulating temperature. Mine has taken a lot of abuse over the years and yet it is still as good as when I bought it - with the exception of a small spot that has a sticky residue from something that had soft glue exposed. That reminds me, I need to clean that up.
They are custom fit. The picture he has at the store page does not really show how well it fits, but it fits very well. So well in fact, that you do not notice it is up there and sometimes forget about it.
I am also lazy and would buy something as long as it is well made and fits my requirements and budget rather than make my own.
If you're handy and would rather make your own, then DOODELEMENT's sunshade is not for you and will, as you said, not be cost effective. For someone like me however, $39 is a great deal.