Jump potion idea

So I see some people complaining about jump potions existing, and others complaining they want more of them.

I think that a person should only be allowed to buy a jump potion after they have leveled a class/job to a certain level.

For example, you are able to buy one jump potion when you level a class to 50. Then, when you level a class to 60 without jump potions, you are able to buy another one, and so-on, with like a max of 4. This way you can get multiple jump potions, but you have to do some work.