Here's my 2 cents:
On inscribable weapons:
Only ones that are worth over 100K are either the exceptional q8 max and for shields the q7 15 armor ones. For aesthetic reasons these are more valuable if dropped as gold instead of purple or blue(gold>purple>blue).
The q9 ones are often merch, though sometimes if it is a genuinely nice skin and not too common you can sell these for 5-15K.
Ofcourse you also have the rare inscr skins that drop from chests at the end of elite areas/dungeons/zchest/hoh; For these there is a price check thread made by ange:
http://www.guildwarsguru.com/forum/s...t10482377.html
(there are as always some exceptions such as the inscr jitte that are not yet included)
On uninscribable weapons:
Now here it gets complicated. Lets start with the physical damage weapons.
q7 which no longer drops since nf release are ofcourse very valuable. these do not need to have these ideal 15^50 inherents to be valuable.
Q8's 15^50, +5e on common skins will often sell for about 20-30ectos. The other inherents on these common skins are not really wanted and are hard to sell.
On rare skins however (sephis axe,mursaat hammer,gothic dual axe,jitte,etc..)
the other inherents will also be valuable, though much less than the 15^50,+5e
example: mursaat q8 15^50 ~300e , 15%ench/15%stance etc ~30e
Q9's are often merch, except if its 15^50 or +5e on one of the rare skins, though these probably wont exceed the price of 100K (jitte being an exception)
In the case of swords and axes however there is also the rare vampiric inherent mod (+15%dmg, -1 health regen) which will be 50-100K on common skins and 100K+ on rare skins. These will often be referred to as dual vamp weapons as they are often combined with a vampiric mod which altogether creates a -2 health degen. On dual handed weapons this vampiric inherent is also possible but not wanted/valuable.
other requirements: same as q9 but with every increase of req comes a decrease in price. The common skins with 15^50 and +5e will then often become a definite merch.
And now it gets even more complicated as we move on to shields,offhands,wands and staves.
Prices of these are very dependent on collectors and general interest, which will often lead to disagreements between the price checkers.
Lets start with shields: As mentioned in previous posts: single mod = merch
(which is also true for wands and offhands)
Obviously there is an exception: (we wouldn't want things to be easy, right?)
+10vs demons single mod is about 10-30K on rare skins. And thats the only exception there is.
dual modded shields: the -5/20% mod is only wanted in combination with +30 hp. (exceptions made for rare skins with good reqs)
This is probably the most valuable combination you can have on a shield. On rare skins these mods do not have to be perfect to be valuable. Imperfection ofcourse kills the price alot but nevertheless a few off on health can still be worth about 50e.
+30hp is good in any combination.
on to the conditional mods: -2st/+45hpst > -2e/+45hp ench > -3hex/+60hp hex
mixtures of these mods (such as -3hex/45hpst) will almost always result in merch, except if on a rare skin with a good requirement.
+10vs mods are good in combination with +30hp,+45hp ench, +45hp stance,-2st and -2e. On rare skins with good reqs -5/20% and -3hex will also be worth a bit.
If +9 instead of +10 the price will drop way more than with +29 instead of +30 or +44 instead of +45.
+10 vs blunt,piercing,demons,undead,earth(and plants) are particularly valuable due to practical demand from ppl playing elite areas. These are most wanted in combination with -2ench, +45hp ench, +30hp (and -2 st to a lesser extent).
there are also the +1attribute 20% mods. These are mainly wanted by collectors and so the second mod they are good with are depending on the personal preferences of collectors, though generally +30hp is most wanted.
There are also some oldschool mod combinations such as -2/-2. (not going into detail on that)
These 'rules' for shields are the same for any requirement. Ofcourse q9 is worth the most and strength is preferred over tactics.
For wands staves and offhands I'm gonna let someone else explain that.