After thinking about this more, my first hammock was made during Boy Scout summer camp in the '60's! A blanket, with nylon rope tied at the ends using sheet bend knots became all the rage and held up to a ton of abuse.
When I sewed my first hammock, I did the same thing with the prototype to get all the tensions right (you want the sides slightly tighter than the middle), so the fabric would lay "just right" before hemming the ends and sides. (the sides are actually ironed hems using "Stitchwitch".
I never really had to sew the final hammock. 4 yards of ripstop, some capable suspension line, sheet bends, done! This would give you the ability to change things around as needed for a custom fit.

My first hammock rain fly was a plastic blue tarp. Again, any coated nylon or sheep plastic will work fine, and be light weight. Learn the "pebble trick" to attach line anywhere on a sheet of fabric/plastic. Before hammocks caught on, this is how it was done.

I bet you could build your own spiffy hammock for under $10, no sewing required! Maybe even free if you look around.