TOPIC: [Dark RP] Mushroom/Weed Npc Change

What would you like to add?:
Replacement of the Drug Dealer npc shop system:

Instead of having a set amount of cash make it infinite but, drugs are now treated as a kind of stock system in which at times the dealer will buy them for varied prices with rare peak points where its recommended you sell then.

Some days he'll buy them only for around 1.5k a mushroom and at peak days it would be 3k, either way he would have a flat amount of money for this.

How would it benefit the server/why do you want this to be added?:

Promote activity for drug dealers to check if the npc is currently having a good price or not
Promote drug dealers not to leave after getting their inventory filled and be unable to sell
Would help flow an economy for trading mushrooms and weed

Could this be exploited in anyway, and if, how could we make it non-exploitable?: Would have to be tested
Additional notes:
N/A

Think about a player based value of his money. It starts at 1 mil, then it takes away whatever you sell to him, and adds $10 every second(800k a day).
Him selling the drugs to you can be similar