I threw away a couple of Vanilla bean skins before I tried making extract. I wasted the ones I threw away. It turns out that it is exceptionally easy to make extract and it's just as good as the bought stuff. I started with a little 100ml empty vanilla bottle, about 4 oz. I had some 190 proof grain alcohol from the duty free store which is perfect because it has no taste of it's own. It's 95% alcohol and I needed about 40% so I just boiled some water and let it cool down then added it to the bottle till I had approximately the correct proportion. Pushed a vanilla skin in and it took about 2 weeks for flavor to fully develop but that is faster than I expected.
I just mixed up a new 250ml bottle and with 2 of those going I should have a constant source of vanilla extract. I used up the last grain alcohol so next time I'll have to use vodka. No need to water down Vodka but that makes it a lot more expensive.