Currently, rupee transactions are not recorded if they are worth 0 rupees. I think it would be useful to add at least an option to record these transactions (for example, under /ps). I sell several dozen items for free, so adding this would make inventory management easier since I won't have to manually check each shop. I know there are also other places like public farms that sell items for 1r instead of 0r to track items.
If this is still up for discussion, I second the idea. Perhaps it could be a toggle option? like turning off shop notifications for certain smps.