I would definitely buy three or four razors to "experiment" on. Antique store and ebay razors can be had cheap, but they sometimes come with problems that beginner honers (like me) cannot figure out. If you get one in good shape, that is an excellent tool to practice on.

If you have some more disposable income, you can try to find a sale and purchase a cheaper new production razor like a Dovo Best and practice on that. That is what I am currently doing and it takes the guess work out.