I’m within the technique of setting a brand new “subscribe & save” e-commerce retailer for a selected product that may change price/worth pretty often. I’m questioning if I’m overthinking this… or occupied with it solely incorrect.

I don’t need to break any guidelines so, for the sake of the publish, let’s name them Widgets.

Final month, I purchased a pallet of Widgets that price me $200 every. This month, the pallet of the identical Widgets price me $300 every. Subsequent month, the Widgets may cost extra… they could price much less… it’s solely depending on provide and demand. My prospects (and this business) understands that idea.

As I setup the shop software program (presently tinkering with Rails+Solidus however open to options), I’m considering that I would like to trace the price of the stock as I obtain it in. And that I must promote it in first-in-first-out order.

In different phrases:

1. At any given time, the stock readily available may have a value and a worth. A consumer will signup for the subscription which entitles them to a sure share off the worth.
2. Subsequent month, upon renewal, we’ll invoice them for the worth of the following accessible Widget in stock. (If the Widget’s worth is the same as or lower than final month’s worth, we’ll course of usually. If the Widget’s worth is increased than final month, we’ll ship an electronic mail permitting the consumer to skip that month.)

Anyway, my questions:

1. Am I overthinking (or underthinking this)?
2. Does anybody else have expertise promoting one thing equally? What do you want you’ll have recognized once you began?