What's going on SRL, so this guide is going to be really simple but good for some low level fast cash. So DONT hate because this isn't for the people that established a better method already.
So here's what we're doing. We'll be buying cowhides, tanning them to leather, and selling the leather back.
To start I'd recommend 50k. And I'll show you the calculations down below.
For 1 cowhide is currently 220gp (no duh this will change)
For 1 leather is currently 348gp (once again this WILL change)
For tanning the cowhides will be 3gp per hide (THIS DOESNT CHANGE UNLESS YOU TAN DRAGON HIDES)
here's the profit calculation
220x27+81=6,021gp (this is how much it is per inventory plus tanning costs)
348x27 =9,396gp (this is how much you make per inventory of leather)
=3,375gp PROFIT!!!!!
I'm sure there's way better methods but starting out this will help you out very much. I hope this guide was helpful and please don't hesitate to ask questions