First of all prices here arn't supposed to be 100% correct!
I created this list to help ppl to Sell/Buy items for a correct price.
Because I saw many ppl which asked for the price of an item which have a “constant” price on the market (more or less), I made this list that no one must ask again and again for such items.

Prices here are only an average of prices which ppl offer normaly or has been added due to the help of people who posted here.

If you find some mistakes please let me know, I will make my corrections.

It is your choice if u believe my price checks or not.

If u have a question concerning prices, i or other players will help u
This new thread is like the old but here i also have a list of items.
The old one:
The Price Check [thread] (old)

Upgrade Core/Force Core/ Slot extenders/ Kit:
=> Upgrade: Low ~ 150k / Medium ~ 400k / High ~ 700k / Highest ~ 5kk / Perfect - No price atm
=> Force: Low ~ 50k / Medium ~ 50k / High ~ 150k / Highest ~ 200k
=> Core Enhancer ~ 6kk
=> Slot Extenders: Low ~ 12kk / Medium ~ 26kk / High ~ 2kkk
=> Coating Kit: Normal ~ 35kk / Perfect – No price atm

Epaulettes & Costumes:
=> Guardian: +3 ~ 1kk / +4 ~ 1kk / +5 ~ 300k / Shadow +5 ~ 6kk / +6 ~ 1kk / +7 ~ 250kk / +8 ~ 2.5kkk
=> Fighter: +3 ~ 1kk / +4 ~ 1kk / +5 ~ 300k / Shadow +5 ~ 19kk / +6 ~ 3kk / +7 ~ 1.1kkk / +8 – No price atm
=> Sage: +3 ~ 1kk / +4 ~ 1kk / +5 ~ 300k / Shadow +5 ~ 8kk / +6 ~ 1kk / +7 ~ 900kk / +8 – 5.5kkk
=> Nightwalkers: lvl 30 (Battle/Matrial/Armor) ~ 35kk/ lvl 50 ~ 50kk
=> Costumes: Vampire ~ 400kk / Halloween Dress ~ 150kk

Boards & Bikes:
=> Boards: Green ~ 80kk / Blue ~ 80kk / Silver ~ 300kk / Black ~ 300kk / Red – 350kk / Yellow - Priceless
=> Bikes: Blue ~ 450kk / RW3 ~ 2kkk

Bracelets:
=> Adept: +0 ~ 50k / +1 ~ 80k
=> Sage : +0 ~ 900k / +1 ~ 1kk / +2 ~ 1kk / +2 with in amp slot ~ 100kk / +3 ~ 10kk / +3 with amp in slot ~350kk / +4 ~ 40kk
=> Fighter : +0 ~ 1kk / +1 ~10kk / +2 ~ 5kk / +2 with in amp slot ~ 160kk / +3 ~ 20kk / +3 with amp in slot ~ 550kk / +4 ~ 125kk

Earrings:
=> Bless: +0 ~ 50k / +1 ~ 80k
=> Vital: +0 ~ 500k / +1 ~ 200k / +2 ~ 1kk
=> Guard : +0 ~ 1kk / +1 ~ 2kk / +2 ~ 3kk / +3 ~ 9kk / +4 ~ 40kk
=> Vampiric Earring: +0 ~ 1kk / +1 ~ 2kk / +2 ~ 4kk / +3 ~ 9kk / +4 ~ 45kk

Amulets:
=> Adept: +0 ~ 100k / +1 ~ 150k / +2 ~ 300k / +3 ~ 3kk
=> Guard: +5 ~ 1.5kk / +6 ~ 2.5kk / +7 ~ 5kk / +8 ~ 8kk
=> Battler: +6 ~ 35kk / +7 ~ 60kk / +8 ~ 80kk
=> Pain: +4 ~ 25kk / +5 ~ 50kk

Rings:
=> Adept: +0 ~ 100k / +1 ~ 150k / +2 ~ 300k / +3 ~ 3kk
=> Luck: +1 ~ 4kk / +2 ~ 70kk
=> Fighter: +7 ~ 500k / +8 ~ 10kk / +9 ~ 60kk
=> Sage: +7 ~ 400k / +8 ~ 10kk / +9 ~ 40kk
=> Champion: +7 ~ 500k

Dungeon/World entery items:
=> Map Part: Normal ~ 500k
=> Muster Card Ruina Station: Normal ~ 350k
=> Epaulette of Dead: B1F ~ 500k / B2F ~ 2kk
=> Seal of Darkness: ~ 4kk
=> Forgotten Temple (B1F): Normal ~ 1.5kk / B2F ~ 4kk

Potions:
=> Extract: Str ~ 50k / Dex ~ 50k / Int ~ 50k

Titanium Equipment:
=> Titanium Helm (any set): 1 Slot ~ 400k / 2 Slot ~ 20kk
=> Titanium Suit (any set): 1 Slot ~ 400k / 2 Slot ~ 5kk
=> Titanium Gloves (any set): 1 Slot ~ 400k / 2 Slot ~ 3kk
=> Titanium Boots (any set): 1 Slot ~ 400k / 2 Slot ~ 4kk

Osmium Equipment:
=> Osmium Helm (any set): Clean ~ 50k / 1 Slot ~ 250k / 2 Slot ~ 1kk
=> Osmium Suit (any set): Clean ~ 80k / 1 Slot ~ 150k / 2 Slot ~ 500k
=> Osmium Gloves (any set): Clean ~ 50k / 1 Slot ~ 100k / 2 Slot ~ 1kk
=> Osmium Boots (any set): Clean ~ 50k / 1 Slot ~ 100k / 2 Slot ~ 800k

99 Equipment:

=> Mystic Helm: Clean ~ 400k / 1 Slot BL: ~ 2kk / 1 Slot WI: ~ 2kk / 2 Slot: ?
=> Mystic Suit: Clean ~ 400k / 1 Slot BL: ~ 2kk / 1 Slot WI: ~ 2kk / 2 Slot: ?
=> Mystic Gloves: Clean ~ 400k / 1 Slot BL: ~ 3kk / 1 Slot WI: ~ 3kk / 2 Slot: ?
=> Mystic Boots: Clean ~ 400k / 1 Slot BL: ~ 2kk / 1 Slot WI: ~ 2kk / 2 Slot: ?
=> Teragrace Helm: Clean ~ 400k / 1 Slot FA: ~ 2kk / 1 Slot FB: ~ 2kk / 2 Slot: ?
=> Teragrace Suit: Clean ~ 400k / 1 Slot FA: ~ 2kk / 1 Slot FB: ~ 2kk / 2 Slot: ?
=> Teragrace Gloves: Clean ~ 400k / 1 Slot FA: ~ 3kk / 1 Slot FB: ~ 3kk / 2 Slot: ?
=> Teragrace Boots: Clean ~ 400k / 1 Slot FA: ~ 2kk / 1 Slot FB: ~ 2kk / 2 Slot: ?
=> Shineguard Helm: Clean ~ 400k / 1 Slot WA: ~ 2kk / 1 Slot FS: ~ 2kk / 2 Slot: ?
=> Shineguard Suit: Clean ~ 400k / 1 Slot WA: ~ 2kk / 1 Slot FS: ~ 2kk / 2 Slot: ?
=> Shineguard Gloves: Clean ~ 400k / 1 Slot WA: ~ 3kk / 1 Slot FS: ~ 3kk / 2 Slot: ?
=> Shineguard Boots: Clean ~ 400k / 1 Slot WA: ~ 2kk / 1 Slot FS: ~ 2kk / 2 Slot: ?

Swords:
=> Shadowtitanium Daikatana: 1 Slot ~ 400k / 2 Slot ~ 20kk
=> Shadowtitanium Great Sword: 1 Slot ~ 400k / 2 Slot ~ 20kk
=> Shadowtitanium Blade: 1 Slot ~ 200k / 2 Slot ~ 50kk
=> Shadowtitanium Katana: 1 Slot ~ 200k / 2 Slot ~ 45kk
=> Osmium Daikatana: 1 Slot ~ 3.5kk / 2 Slot ~ 20kk
=> Osmium Great Sword: 1 Slot ~ 3.5kk / 2 Slot ~ 30kk
=> Osmium Blade: 1 Slot ~ 2kk / 2 Slot ~ 60kk
=> Osmium Katana: 1 Slot ~ 2kk / 2 Slot ~ 55kk
=> Redosmium Great Sword: 1 Slot ~ 4kk / 2 Slot – No price atm
=> Redosmium Daikatana: 1 Slot ~ 3.5kk / 2 Slot ~ 170kk
=> Redosmium Blade: 1 Slot ~ 3kk / 2 Slot ~ 200kk
=> Redosmium Katana: 1 Slot ~ 2.5kk / 2 Slot ~ 180kk

Orbs/Crystals:
=> Aqua Orb: 1 Slot ~ 200k / 2 Slot ~ 50kk
=> Aqua Crystal: 1 Slot ~ 200k / 2 Slot ~ 45kk
=> Lapis Orb: 1 Slot ~ 1.5kk / 2 Slot ~ 80kk
=> Lapis Crystal: 1 Slot ~ 1.5kk / 2 Slot ~ 75kk
=> Topaz Orb: 1 Slot ~ 2kk / 2 Slot - No price atm
=> Topaz Crystal: 1 Slot ~ 2kk / 2 Slot ~ 230kk

2 Slot item drop items:

Quote:
Originally Posted by Lord Seru 

Rings:
+0 100k-150k
+1 250k-500k
+2 500k-750k
+3 3kk-3.5kk
+4 10kk-12.5kk
+5 90kk-100kk
+6 150kk-175kk
+7 the ony one i ever saw was 1kkk, so no real price to guess

Amulets:
+0 100k-200k
+1 400k-500k
+2 600k-700k
+3 5kk-6kk
+4 7kk-8kk
+5 40k-50kk
+6 100kk-150kk
+7 500kk-600kk (O_O just seen one for 315kk so i'm not sure about this price...)

Bracelets:
+0 250k-300k
+1 1kk-1.5kk
+2 500k-750k
+3 5kk-6kk
+4 20kk-30kk

Earrings:
+0 250k-300k
+1 1kk-1.5kk
+2 500k-750k
+3 5kk-6kk
+4 20kk-30kk

Formula Cards:
=> 1. HP Potion(LV 2) 40k (shop in port lux)
=> 2. HP Potion(LV 3) 40k (shop in port lux)
=> 3. MP Potion(LV 2) 40k (shop in port lux)
=> 4. MP Potion(LV 3) 40k (shop in port lux)
=> 5. Epaulet of Proof 40k (shop in port lux)

=> 6. Concentration Potion(LV 1) ~ 3kk
=> 7. Reflex Potion(LV 1) ~ 3kk
=> 8. Vital Potion(LV 1) ~ 3kk
=> 9. Sharpness Potion(LV 1) ~ 3kk
=> 10. MP Condensation Potion(LV 1) ~3kk
=> 11. HP Potion(LV 2) 40k (shop in fort ruina)
=> 12. HP Potion(LV 3) 40k (shop in fort ruina)
=> 13. MP Potion(LV 2) 40k (shop in fort ruina)
=> 14. MP Potion(LV 3) 40k (shop in fort ruina)
=> 15. Epaulet of Proof+1 40k (shop in fort ruina)

=> 16. Vital Regeneration Potion(LV 1) ~ 4kk
=> 17. ??? (doesn't exist yet)
=> 18. Hardness Potion(LV 1) ~ 4kk
=> 19. Strike Potion(LV 1) ~ 4kk
=> 20. ??? (doesn't exist yet)
=> 21. ??? (doesn't exist yet)
=> 22. Return Stone 40k (shop in fort ruina)
=> 23. HP Potion(LV 2) ~ 3kk
=> 24. HP Potion(LV 3) ~ 3kk
=> 25. MP Potion(LV 2) ~ 3kk
=> 26. MP Potion(LV 3) ~ 3kk
=> 27. ??? (doesn't exist yet)
=> 28. ??? (doesn't exist yet)
=> 29. ??? (doesn't exist yet)
=> 30. Epaulet of Proof +2 40k (shop in fort ruina)

=> 31. ??? (doesn't exist yet)
=> 32. Fury Potion(LV 1) ~ 1kk
=> 33. Concentration Potion(LV 2) ~ 5kk
=> 34. Reflex Potion(LV 2) ~ 5kk
=> 35. Vital Potion(LV 2) ~ 5kk
=> 36. Sharpness Potion(LV 2) ~ 5kk
=> 37. MP Condensation Potion(LV 2) ~ 5kk
=> 38. HP Potion(LV 2) ~ 4kk
=> 39. HP Potion(LV 3) ~ 4kk
=> 40. Return Stone ~ 4kk
=> 41. MP Potion(LV 2) ~ 4kk
=> 42. MP Potion(LV 3) ~ 4kk
=> 43. ??? (doesn't exist yet)
=> 44. ??? (doesn't exist yet)
=> 45. ??? (doesn't exist yet)
=> 46. ??? (doesn't exist yet)
=> 47. ??? (doesn't exist yet)
=> 48. ??? (doesn't exist yet)
=> 49. ??? (doesn't exist yet)
=> 50. Epaulet of Proof +3 ~ 80kk

=> 51. Upgrade Core(Crystal) ~ 3.5kk
=> 52. Force Core(Crystal) ~ 3.5kk
=> 53. Extract Potion(STR) ~ 2.5kk
=> 54. Extract Potion(DEX) ~ 2.5kk
=> 55. Extract Potion(INT) ~ 2.5kk
=> 56. C.A Unit - Regard for H.Age ~ 1kk
=> 57. ??? (doesn't exist yet)
=> 58. ??? (doesn't exist yet)
=> 59. ??? (doesn't exist yet)
=> 60. Good Luck Potion(LV 1) ~ ?
=> 61. ??? (doesn't exist yet)
=> 62. ??? (doesn't exist yet)
=> 63. Vital Regeneration Potion(LV 2) - ?
=> 64. ??? (doesn't exist yet)
=> 65. Hardness Potion(LV 2) - ?
=> 66. Strike Potion(LV 2) - ?
=> 67. ??? (doesn't exist yet)
=> 68. ??? (doesn't exist yet)
=> 69. ??? (doesn't exist yet)
=> 70. ??? (doesn't exist yet)
=> 71. ??? (doesn't exist yet)
=> 72. ??? (doesn't exist yet)
=> 73. ??? (doesn't exist yet)
=> 74. ??? (doesn't exist yet)
=> 75. Epaulet of Proof +4 ~ 15kk

=> 76. Upgrade Core(LV 1) ~ 1kk
=> 77. Plasma Circuit ~ 120kk
=> 78. Extender Circuit ~ 120kk
=> 79. Glory Potion(LV 1) - 100kk
=> 80. Astral Core Mithril ~ 1kk
=> 81. Good Luck Potion(LV 2) ~ 5kk
=> 82. ??? (doesn't exist yet)
=> 83. ??? (doesn't exist yet)
=> 84. Fury Potion(LV 2) ~ 3kk
=> 85. Concentration Potion(LV 3) ~ 5kk
=> 86. Reflex Potion(LV 3) ~ 6kk
=> 87. Vital Potion(LV 3) ~ 6kk
=> 88. Sharpness Potion(LV 3) ~ 5.5kk
=> 89. MP Condensation Potion(LV 3) ~ 5.5kk
=> 90. ??? (doesn't exist yet)
=> 91. Plasma Plug ~ 1kk
=> 92. ??? (doesn't exist yet)
=> 93. ??? (doesn't exist yet)
=> 94. ??? (doesn't exist yet)
=> 95. Epaulet of Proof +5 ~ 300kk

=> 96. Upgrade Core (Medium) ~ 1kk
=> 97. Slow extender (Low) ~ 1.5kkk
=> 98. Sword Master Potion ~ 15kk
=> 99. Magic Master Potion ~ 15kk
=> 100. Astral Core (Blue Mithril) ~ 1kk
=> 101. Glory Potion (lvl2) ~ 100kk (not sure)
=> 102. ??? (doesn't exist yet)
=> 103. Evasion Potion ~ 50kk
=> 104. Vital Regeneration Potion(LV 3) ~ 8kk
=> 105. ??? (doesn't exist yet)
=> 106. Hardness Potion(LV 3) ~ 8kk
=> 107. Strike Potion(LV 3) ~ 8kk
=> 108. ??? (doesn't exist yet)
=> 109. ??? (doesn't exist yet)
=> 110. Epaulet of Proof +6 ~ 1kk

=> 111. Force Core (High) ~ 1kk
=> 112. Upgrade Core (High) ~ 1kk
=> 113. Plasma Coating Kit ~ 15kk
=> 114. Slot Extender(Medium) ~ 200kk
=> 115. ??? (doesn't exist yet)
=> 116. Glory Potion(LV 3) ~ 100kk
=> 111. Epaulet of Proof +7 ~ 1kk

Prof. Craft:
=> Dark Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 20k / lvl 3 ~ 450k / lvl 4 ~ 2kk
=> Thunder Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 20k / lvl 3 ~ 200k / lvl 4 ~ 2kk
=> Flame Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 30k / lvl 3 ~ 400k / lvl 4 ~ 900k
=> Holy Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 10k / lvl 3 ~ 200k / lvl 4 ~ 500k
=> Earth Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 10k / lvl 3 ~ 200k / lvl 4 ~ 500k
=> Bloody Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 10k / lvl 3 ~ 200k / lvl 4 ~ 500k
=> Air Discs lvl 1 - Core Alchemist (PL) / lvl 2 ~ 20k / lvl 3 ~ 200k / lvl 4 ~ 500k

=> Shape (Sword) lvl 1 - Core Alchemist (BI,DS,GD) / lvl 2 ~ 50k / lvl 3 ~ 600k / lvl 4 ~ 1kk
=> Shape (Armour) lvl 1 - Core Alchemist (BI,DS,GD) / lvl 2 ~ 50k / lvl 3 ~ 800k / lvl 4 ~ 4kk
=> Shape (Matrial) lvl 1 - Core Alchemist (BI,DS,GD) / lvl 2 ~ 50k / lvl 3 ~ 600k / lvl 4 ~ 5kk
=> Shape (Battle) lvl 1 - Core Alchemist (BI,DS,GD) / lvl 2 ~ 50k / lvl 3 ~ 500k / lvl 4 ~ 3kk
=> Shape (Artifact) lvl 1 - Core Alchemist (BI,DS,GD) / lvl 2 ~ 50k / lvl 3 ~ 1kk / lvl 4 ~ 4kk

The List will be upgraded frequently!