I have now started working again on the shop manager. The first thing now finalized is the “Goods” category, where you can now lookup all items in the shop, and by clicking on them you can dive into sub-items (if available) and see all requests and offers for the final block.
Currently we are structuring this according to the data hierarchy as it is programed into minecraft. Thus, different wool types are a sub-type of wool, but some of the blocks like Podzol might not be so easy to find if you do not know what they are a sub-type of. I will be working on an alternative model in the future to make it a bit more user-friendly.