i have stockpiled a lot of materials. I am guessing that crafting and then selling would get more profit than just selling them.
So what items would sell for a lot if i get a good UV?
which items to craft?
Brandishes are probably easiest to get useful UVs on, since they can be upgraded to deal either Shadow or Elemental damage (Cautery still sucks). This means that pretty much any damage-bonus UV won't be completely useless if generated on a 2* Brandish. A Brandish with the right level of damage bonus (high or very high) will sell very well. CTR and ASI bonuses, though, are generally more favoured.
On most other weapons, the primary attractions are CTR/ASI bonuses, where appropriate. Autogun line guns will generally favour CTR since that's the attraction of the weapon. With Sealed Swords, both ASI and CTR are fairly equally valued. Status-type alchemers are generally more valuable with ASI on them. In the case of bombs, CTR can be extremely valuable.
Please note that damage-boosting UVs on haze-type bombs (those which leave a mist that inflicts a status) are almost completely useless, since it only boosts the damage of the initial explosion. They will rarely, if ever, add any value onto the sell price of a bomb.
On armour, damage protection UVs are okay but not generally considered that great. Good (high or max) Shock and Fire status resistances are very valuable, and Freeze and Stun are also sought after (this latter being used in Lockdown matches). Poison is also reasonably useful, and people may look for extra poison resistance for a specialist set (coughCompound42cough). Curse is generally the least wanted resistance, since there are few sources of Curse in normal play. (Curse is inflicted on players by: Carnavons, found only in SL FSC or, rarely, in Candlestick Keep; Cursed Deadnaughts, found in the last level of the LoA Danger Mission and the SL FSC; Phantoms, found in Graveyard levels; and self-inflicted by the charge attack of Faust/Gran Faust.)
Good-selling, craftable 2* items:
Wolver (Cap, Coat), Magic (Hood, Cloak), Owlite Shield, Plate Shield, Flourish, Brandish, Autogun
Avoid crafting for sale unless upon request as these are much more difficult to sell:
Spur, Cobalt-line items (all available as mission rewards), Toxic Vaporiser, Haze Bomb, Crystal Bomb, Plate set (non-shield)
Almost anything will sell well if it has a good UV. But when you don't get UVs, you should probably sell them on AH. Other than masks of Seerus, profitability constantly changes. Find something that not many people make. You can sell some 3* items or 20-25k. I usually put mine for 22k or 23k, or less than whatever else is on AH.