How to know the value of mods/upgrades...?

First of all, I'm sorry if it isn't the correct sub-forum for posting it.

I know almost everything about GW, I expect completing my HoM before GW2 releases, but I need money for that.

I had some upgrade weapons/insignias/mods, etc. in my storage. I've heard a lot of times: "oh, this is so expensive" and "this is worth nothing, sell it to merchant".
But I don't know which ones are so valuable and which ones aren't.

Is there any guide around internet from which I could learn something about all this? What can I do?

Thank you for your help (and excuse me for my English).

1: for insignia's and runes, you can simply go to a rune trader (in towns and maybe your Guildhall). If the rune trader npc e.g. sell's the rune you have for 1000 gold and buys it for 500 gold, then the market value of the rune is mostly always 750g (right in the middle). That way, when trading directly to a player, you both get half of the profit compared to when you sell to the rune trader and the other party has to buy it there.

2: for weaponmods this doesn't count cause they aren't for sale at an npc. Best way to know the price is to check the trade channel in Kamadan or use the trade section on this forum to find out what others are buying and selling the item for. Another usefull source can be http://www.argos-soft.net/GwEstimator/. This site keeps record of the trade channel in Kamadan and makes it searchable.

If the item can't be found in any of these sources it is prolly not worth a lot. But when in doubt you can always use the pricecheck section of this forum to ask the community.

Just to add to that, you'll find that certain mods are usually in demand while others almost never are. Mods that cause extra damage, give extra health or energy or provide extra armor unconditionally (or with a very easily met condition) are usually worth something as long as the bonus they're giving is maxed. See the wiki entry on weapons mods to see what max is.

Max Vampiric, Zealous and (for some reason) sundering are also valuable. Things that extend poison, bleeding, etc. are usually not worth anything (though crippling and silencing can be nice for PvP). For spellcaster weapons (focus, etc.) things that give god chance of HCT or HRT are usually worth something as well.

Also, to add to that, any mod, Rune or Insignia that is less than "max" is basically worthless. For example, a 19% sundering or 2/-1 Vampiric mod.

Btw, ignore the above "for some reason" comment about Sundering. There has always been much discussion about Sundering vs Vampiric mods, and the psuedo-leets like to try to make it sound like Vampiric is "god's gift" while Sundering is trash. The truth is that there is very little (if any) real difference between them - particularly in PvE - so use whichever floats your boat.

Runes/Insignia's check rune traders till you get comfortable knowing which ones are worth more or less. Sell to rune trader after salvage.

Mods... mods are tricky. My best advice is to get on argos-soft.net and see if your mod is worth anything. There are quite a few mods, and without writing a small novel it will be hard to go into any detail as to which ones are worth anything. Here's the gist of it though.

+5e/15^50 for martial weapons
20% hsr/hct for caster (sometimes +5e^50%health)
20% hsr/hct for staves

shields
+30/45 ench
-5(20%)/-2ench
+10 Armor vs (anything)

20% longer enchant, zealous, furious, sundering, vampiric, health +30 Those mods are almost always worth something. Sometimes fiery, cold, earth, lightning mods are worth something as well.

The best way to know though is to watch. Go to kama and see what others sell at. (or use argos)

I liked ur post, I needed some reference as this one, but if someone could explain me what do things like "hsr", "hct", "^", etc. I would be so grateful

15^50: Bonus 15% damage while health is above 50%
HSR: Halves Skill Recharge
HCT: Halves Casting Time

It is a bit more complicated than that mind; So while the above comments are a good guide don't take them as absolutes over what's worth keeping and what's not.

For example 20% enchant lengthening is in very high demand for Staffs and Spears, and I've seen them sell for 20k+ (albeit typically they'd sell for about half that).

While it's still popular, but in slightly less demand, there is normally people looking for 20% enchantment lengthening for Swords and Scythes too.

Axes and Daggers come as runners up, though you might still find the odd buyer who wants it for their Chaos Axe on their Monk or some perma-shadow forming on a non-caster Assassin.

You'll have a very hard time however selling 20% enchantment lenghtening for Bow or Hammer; And in these cases it's probably not worth holding onto them unless you plan to use them yourself or see an instant buyer when you return to town with them.

Yeah agreed with KotCR....mods are very item dependent. Zealous mods, for example work great for a scythe as the scythes ability to hit multiple targets at once increases the "plus" side of the mod. On a hammer however, due to the hammers slow attack rate, it becomes near useless. Zealous scythe mid as a result can go upwards of 8k while you wouldnt be able to find a buyer for a zealous hammer mod for even what youd get if you just merched it.

On topic: the best way would be if you can get into experienced guild or if you have experienced friends who could advise you on prices. The other way is using Argos Soft (you can just google it) but you should be careful with that, as prices are often manipulated.