For now, I'm against adding any fluctuating prices or randomness features, because randomness can be achieved through other modding features. Similarly, I think a custom reset interval is unnecessary. If, for instance, you wanted the interval to be 10 days, well, that's same as limit of 3 per month. If you wanted the interval to be 10 months, then that can be achieved through manufacture that requires 10 material items with availability of 1 per month. Altho... a possible solution involves allowing decimal numbers for monthly availability of items/soldiers/craft. For instance, if the modder sets "monthlyBuyLimit" of an item to be 0.1, then each month 0.1 is subtracted from the item's "boughtCounter". So after 10 months, the "boughtCounter" would reach 0 and the item would be available for purchase again.