I'm making a bifold wallet with the dimensions to fit up to UK-currency (Maximum bill height 85mm)
I will update with some photos during the construction. I start with some drawings and a couple of photos, and will add a couple of more photos until it's finished. Ask if you have any questions. (Disclaimer: Self taught hobbyist, so construction methods are what works for me)
Some information about materials used.
Exterior leather: Black vegetable tanned semi-aniline