My idea is to add an optional feature to the shop plugin to allow variable quantity chests. 

I'm not sure how complex the code is but adding the possibility to specify the quantity on line 2 and then use math to determine the purchase price for a slot would be cool. 

For example:

Line 1: $

Line 2: 1 diamond_block

Line 3: 1 netherite_ingot

Now, when the owner stocks the chest the could put any number of diamond blocks in each chest slot. When the buyer clicks a slot the plugin calculates the cost. for example if a slot has 4 diamond blocks in it the purchase price is 4 netherite ingots.

Nice idea, but then youd 'have to make code to prohibit anything but what the code specifies to be put in the chest by the owner. Main challenging thing imo is enabling this behavior while also enabling the regular behavior.

Gan is correct, the system works pretty well now, and we don't want to add additional complexity where not necessary as it increases the odds something will break. However, it has been escalated to Coral and Red to consider the difficulty of adding this. If it's simple, maybe it's worth it! I’ll add this for review and post an update after the next meeting.