I'd be tempted to design flat-pack furniture that doesn't rely on hard-to-find metal fastenings.
My daughter lives by flat-pack and because she doesn't have a man about the house any more she assembles it herself. (Except when she persuades me to do it.) She's usually in too much of a hurry to make stuff properly although I have shown her how to use basic tools.
As for the flat-pack stuff, she complains about
Panels that warp after a few weeks in the house.
Metal fixings that break and can't be replaced without going to source.
Limiting designs.
Confusing instructions for assembly.
The other day I helped her dissemble a wardrobe so she could get it into the bedroom of her new house.
The thing went back together much quicker than it came apart, believe me, so maybe experience helps!
However, there were some weird, rough and ready metal fixings on that, and the staples that secured the back in place were just about re-usable.
I hope that little list goes some way to helping you with things to avoid.
I know it's going to be difficult to design knock-down furniture without metal hardware, but maybe it could be done using a minimum of off the shelf, easily sourced fittings. (And PLEASE! Use thicker timber than is the norm! )
HTH
John
