Evolve price list in time
In some case, a company could want to plan the price list changes over time instead of in real-time.
So I propose to create a module that adds start/end dates on the price list line. Those date will be used to compute an active field based on contextual date (default today).
But also to ease the management, I propose to replace the one2many lines with a relate using a view with a context (for the date). Like that user could see the price list at any date.