how about a fillable item that gets full with an interaction to a nurse or something, and has number of uses till gets empty, like has 5 uses with 100hp per. so it should be expensive item

In that sense, wouldn't just buying 5 Hyper potions be better?

 

And you can find nurse joy around in popular caves, which can heal your Pokemon for 2500.

 

Is there any way you can elaborate more? Like give a good example on how to utilize your idea?

I.e You can choose to use 3 out of 5 charges in a single turn when healing a Pokemon.

so u can fill it in that caves by joy one time to

its just and idea, u decide good or bad, i think its a good item to keep in shortcut slots like mounts 

 -1, pokemarts are always useful money sinks, they're simple and reliable, and offer numerous different healing options for you to buy already. If you run out, you just have to buy more

-1, dont see the need for that as we can just use potions and other healing items/options.