I use ~waka and ~Priscilla for values but will occasionally disagree with them. I usually focus on my high priority wishes almost exclusively, so I can sometimes refuse fair offers for some of my items, especially if they are HTPW or if I intend to use them as fodder for higher priority items. I always try to reply to NM offers even if I refuse them; if I haven't replied to yours I've likely forgotten or missed it. If my NM is full please send me a Foal in Box to let me know.
These are items I have and am not currently using on customizations, but which I really like (regardless of value) and am not as inclined to trade away. Numbers are what I value them at.
These are items that are new and/or whose value is still undetermined. I'm unlikely to trade these away for now unless I offer them or you offer a high priority wish or very valuable item.
These are the items I currently want the most. Am willing to do GBCs and custom trades for them.
These are items for future customizations I'm not actively working on at the moment. Way less likely to accept offers for them right now.
These are just items I think are pretty or want to keep track of for some reason. Less likely to accept trades for them.
These are items I want for one of my galleries, not for customizations. This means they are currently the LOWEST priority for me, and so I am more likely to refuse offers for them because customization items are usually much higher priority for me.