[Lawtan]

I mean, 1 month old discontinued rune items are still generally ~20 runes or the equivalent in aurum (4000-5000). I assume after that, price increases to somewhere between the old stuff and the initial value.

The more you can do/more variety an item has, the more it's worth as well.

2012/2013 donation stuff seems around 8-18k aurum. Event items from that period are around 3-8k aurum. 2010/2011 donation/special items seem more 10-30k. So, 2014/2015 donation items may be 5-7k aurum, and event items 2-5k.

I don't think rarity comes into play as we don't know how many of each item was bought on Trisphee before it went out of circulation.

(Just speculation)