MapleStory/Quests/Exchange Quest

There's a man in Orbis named Staff Sergeant Charlie who is accepting etc drops from specific Ossyria monsters for 500 experience and will give you some rewards.

A list of the tradable items and possible rewards is already compiled on Hidden-Street here.

Some items are more efficient when comparing the gained exp to the exp gained while hunting the monsters. Specifically, the Solid Horns from the Jr. Kitties have the best ratio, as the only other monsters weaker in Ossyria are not accepted in the exchange quest. Other items, like Bain Collars and Lycanthrope Toenails, are merely a novelty exchange, as the reward likely pales in comparison to the items gained while hunting down the monsters.

Some items are also bought in large quantities in use of leveling lower level characters. Though a character leveled by this method needs to be a minimum level 10 to reach Orbis, training is incredibly fast, gaining 500 exp in a matter of seconds. At higher levels, however, this method becomes less efficient. Eventually the exchange becomes merely a way to clear useless etc items for usable items, though selling them for pure meso is always an option. Solid horns are usually preferred to level up a lower-level character, due to the number of players training on the Jr. Kitties at any one time. Zombie Teeth are more expensive, but the chance of getting a Fairy Wing as a reward can offset this extra cost. Also, players train on Zombies far longer than Jr. Kitties. Jr. Yeti Skins fall in between, more expensive from a higher-level monster, and providing better potions than Solid Horns, but nothing too special.

Every exchangeable etc item has a specific scroll type (usually 10%) that has a small chance of being given as a reward for a trade-in. However, there are a few exceptions. Solid horns provide Return to Nearest Town scrolls, while Luster Pixie's Sunpieces provide the expensive 60% Cape INT scroll, contributing to the higher-than-average Sunpiece price. Some trade-ins also have special rare items. Notable examples are Ancient Scrolls from Hector Tails, Icicles from Werewolf Toenails (though rarely traded in), and the aforementioned Fairy Wings from Zombie's Lost Teeth.

In the area known as Zipangu, there is another exchange quest with the possibility of obtaining cursed scrolls. The prize rate is far lower for this exchange, however. The availability of many items to turn in and its location on Victoria Island make it a friendlier exchange, however getting out of Showa may prove difficult.

Orbis Exchange Quest
This exchange quest is done in Orbis by talking to Staff Seargent Charlie whom is located in the upper mid-left of town. He’ll accept any level 30+ monster etc drop from monsters in El Nath Mountains (with exception to some etc drops.) By turning in some of these items, the player gains 500 exp in addition to ONE of the following.

100 Solid Horns (from Jr Cellions, Grupins or Lioners)

 * 15 Processed Wood
 * 15 Return Scrolls to Nearest Town
 * 20 Orange Potions
 * 15 Fried Chickens
 * 15 Blue Potions
 * 10 Lemons

100 Star Pixie’s Pieces of Star

 * 20 Processed Wood
 * 40 Meat
 * 30 Orange Potions
 * 20 Blue Potions
 * 1 Scroll for Helmet Def 10% (Rare)

100 Lunar Pixie’s Pieces of Moon

 * 15 Dragon Skins
 * 25 White Potions
 * 10 Mana Elixirs
 * 5 Pure Waters
 * 1 Scroll for Shield Def 10% (Rare)

100 Lustar Pixie’s Pieces of Sun

 * 5 Screws
 * 30 White Potions
 * 15 Mana Elixirs
 * 20 Salads
 * 1 Scroll for Cape Int 60% (Rare)

100 Nepeandath Seeds

 * 30 Processed Woods
 * 15 White Potions
 * 25 Blue Potions
 * 15 Lemons
 * 1 Scroll for Earring Int 10% (Rare)

100 Dark Nepeandath Seeds

 * 5 Screws
 * 30 White Potions
 * 15 Mana Elixirs
 * 20 Salads
 * 1 Scroll for Topwear Def 10% (Rare)

100 Jr Yeti Skins

 * 5 Screws
 * 30 White Potions
 * 15 Mana Elixirs
 * 20 Salads
 * 1 Scroll for Topwear Def 10% (Rare)

100 Dark Jr Yeti Skins

 * 1 Fairy Wing
 * 30 Hot Dogs
 * 15 Hot Dog Supremes
 * 30 Red Bean Soup
 * 1 Scroll for Overall Armor Def 10% (Rare)

100 Yeti Horns

 * 7 Garnet Ores
 * 7 Amethyst Ores
 * 3 Aquamarine Ores
 * 2 Diamond Ores
 * 25 Mana Elixirs
 * 20 Salads
 * 1 Scroll for Shoes Speed 10% (Rare)

100 Dark Yeti Horns

 * 7 Sapphire Ores
 * 7 Emerald Ores
 * 7 Opal Ores
 * 2 Black Crystal Ores
 * 25 Mana Elixirs
 * 1 Scroll for Glove Dex 10% (Rare)

100 Hector Tails

 * 1 Ancient Scroll
 * 15 Warrior Potion
 * 15 Sniper Potion
 * 10 Wizard Potion
 * 1 Scroll for Overall Armor Dex 10% (Rare)

100 White Fang Tails

 * 1 Piece of Ice
 * 7 Silver Ores
 * 7 Adamantium Ores
 * 7 gold ores
 * 1 Scroll for Bottomwear Def 10% (Rare)

100 Pepe Beaks

 * 5 Screws
 * 7 Bronze Ores
 * 7 Steel Ores
 * 7 Mithril Ores
 * 2 Gold Ores
 * 20 Mana Elixirs
 * 1 Scroll for Shoes Dex 10% (Rare)

100 Dark Pepe Beaks

 * 7 Silver Ores
 * 7 Orihalcon Ores
 * 3 Gold Ores
 * 2 Diamond Ores
 * 2 Black Crystal Ores
 * 20 Mana Elixirs
 * 1 Scroll for Shoes Jump 10% (Rare)

100 Werewolf Toenail

 * 7 Topaz Ores
 * 2 Diamond Ores
 * 2 Black Crystal Ores
 * 30 Mana Elixirs
 * 1 set of Icicles
 * 1 Scroll for Glove Atk 10% (Rare)

100 Lycanthrope Toenail

 * 7 Topaz Ores
 * 2 Diamond Ores
 * 2 Black Crystal Ores
 * 30 Mana Elixirs
 * 1 Scroll for Cape Dex 10% (Rare)

100 Flyeye Wing

 * 20 Processed Wood
 * 40 Meat
 * 30 Orange Potions
 * 20 Blue Potions
 * 1 Scroll for Helmet Def 10% (Rare)

100 Jr Cerebes Tooth

 * 30 Processed Wood
 * 15 White Potions
 * 25 Blue Potions
 * 15 Lemons
 * 15 All Cure Potions
 * 1 Scroll for Earring Int 10% (Rare)

100 Firebomb Flames

 * 25 Mana Elixirs
 * 25 Hot Dog Supremes
 * 8 Silver Ores
 * 8 Orihalcon Ores
 * 3 Gold Ores
 * 2 Diamond Ores
 * 2 Black Crystal Ores
 * 20 Mana Elixirs
 * 1 Scroll for Shoes Jump 10% (Rare)

100 Cellion/Grupin/Lioner Tails

 * 5 Screws
 * 30 White Potions
 * 15 Mana Elixirs
 * 20 Salads
 * 1 Scroll for Cape for Weapon Def 10% (Rare)

100 Zombies Lost Teeth

 * 1 Fairy Wing
 * 20 Mana Elixirs
 * 30 Hot Dogs
 * 15 Hot Dog Supremes
 * 20 All Cure Potions
 * 1 Scroll for Cape for Magic Def 10% (Rare)

100 Cerebes Teeth

 * 1 Fairy Wing
 * 25 Mana Elixirs
 * 35 Red Bean Soups
 * 8 Garnet Ores
 * 8 Amethyst Ores
 * 8 Aquamarine Ores
 * 2 Diamond Ores
 * 30 All Cure Potions
 * 1 Scroll for Cape Luk 10% (Rare)

100 Bains Spiky Collar

 * 35 Mana Elixirs
 * 9 Topaz Ores
 * 4 Diamond Ores
 * 4 Black Crystal Ores
 * 1 Scroll for Cape HP 10% (Rare)

Zipangu Exchange Quest
This exchange quest is done in Zipangu by talking to Faito whom is located Showa Town. He’ll accept almost any monster etc drop from monsters in Zipangu. Monster etc drops from Pine Forest and Kaede Castle are an exception. Unlike the Orbis Exchange Quest, the player doesn't gain any exp from handing in items.

100 Crow Feathers

 * 1 Red Potion
 * 5, 10 or 20 White Potions
 * 5, 10 or 20 Blue Potions
 * 1 Mana Elixir
 * 15 Takoyaki (Octopus Ball)
 * 15 Yakisoba
 * 2 Topaz Ores
 * 2 Opal Ores
 * 2 Garnet Ores
 * 1 Purple Bandana

100 Cloud Foxtails

 * 5, 10 or 20 White Potions
 * 5, 10 or 20 Blue Potions
 * 1 Mana Elixir
 * 15 Takoyaki (Octopus Ball)
 * 15 Yakisoba
 * 2 Garnet Ores
 * 1 Pink Bandana

100 Dark Cloud Foxtails

 * 5, 10 or 15 Kinoko Ramen (Pig Bone)
 * 5, 10 or 15 Mana Elixirs
 * 1 Blue Potion
 * 2 Mithril Ores
 * 2 Adamantium Ores
 * 1000 Arrow for Bow [2]
 * 1000 Arrow for Crossbow [2]
 * 1 Grey Work Glove
 * 1 Brown Work Glove
 * 1 Scroll for Overall Str 60%

100 Raccoon Firewood

 * 5, 10 or 20 White Potions
 * 10 Blue Potions
 * 15 Takoyaki (Octopus Ball)
 * 15 Yakisoba
 * 2 Topaz Ores

100 Ghost Headbands

 * 5, 10 or 15 Kinoko Ramen (Pig Bone)
 * 5, 10 or 15 Tempuras (Dish)
 * 15 Ice Cream Pops
 * 15 Red Bean Sundaes
 * 2 Silver Ores
 * 2 Gold Ores
 * 1000 Arrow for Bow [2]
 * 1 Yellow Adventurer Cape
 * 1 Brown Adventurer Cape

100 Littleman A’s Badges

 * 5, 10 or 20 White Potions
 * 5, 10 or 20 Blue Potions
 * 1 Mana Elixir
 * 15 Yakisoba
 * 1000 Arrow for Bow [2]
 * 1000 Arrow for Crossbow [2]
 * 1 Purple Bandana

100 Littleman B’s Nameplates

 * 5, 10 or 15 Kinoko Ramen (Pig Bone)
 * 5, 10 or 15 Mana Elixir
 * 2 Adamantium Ore
 * 1000 Arrow for Bow [2]
 * 1000 Arrow for Crossbow [2]

100 Littleman C’s Necklaces

 * 5, 10 or 15 Kinoko Ramen (Pig Bone)
 * 1, 5, 10 or 15 Mana Elixir
 * 1 Blue Potion
 * 2 Mithril Ore
 * 2 Adamantium Ore
 * 1000 Arrow for Bow [2]
 * 1000 Arrow for Crossbow [2]

100 Leader A’s Shades

 * 5, 10 or 15 Kinoko Ramen (Pig Bone)
 * 5, 10 or 15 Tempuras (Dish)
 * 15 Ice Cream Pops
 * 15 Red Bean Sundaes
 * 2 Gold Ores
 * 1 Brown Adventurer Cape

100 Leader B’s Shades

 * 5 or 15 Kinoko Ramen (Pig Bone)
 * 15 Tempuras (Dish)
 * 15 Ice Cream Pops
 * 15 Red Bean Sundaes
 * 5 Silver Ores
 * 1 Brown Adventurer Cape

100 Boss’s Pomades

 * 5, 10 or 20 Kinoko Ramen (Roasted Pork)
 * 10 or 20 Pure Water
 * 15 Takoyaki Jumbos
 * 1 Mana Elixir
 * 2 Black Crystal Ores