In general, aside from the Secret Laboratory sets, it is probably smarter to sell the pieces, since the rewards for turning the other map sets in are so much less than what it takes to get the map.
Each treasure map consists of 9 seperate pieces. All 9 pieces are
seperate items, meaning they can be traded, bought, sold, donated, etc. just like any other. However, you should keep in mind that when you turn in a map to get your reward, the map set will disappear. Forever! *dun dun dun*
The Original Treasure Map
Prize: 10,000 nps and some rare items.
Secret Laboratory Map
Prize: You get 10,000 nps, plus it opens the door to the secret laboratory ray. The lab ray can be used once per day, forever *dun dun dun*, on one pet only. It will raise or lower your stats, change your pets color, species or gender.
Petpet Lab Ray Map
Prize: Access to the Petpet Lab Ray. (Please note that the petpet lab ray is ONLY accessible if you've already turned in the Secret Laboratory Map) The petpet lab ray can be used once per day, FOREVER, on one petpet only. It will raise or lower your petpets level, change your petpets color, species or name. But, once you unequip your petpet from your pet, it will return to the way it was before to being zapped by the lab ray.
Underwater Map
Prize: 10,000 NP, water food items, and a level up.
Spooky Treasure Map
Prize: 10,000 NP and some random spooky foods.
Space Map
Prize: 10,000 NP and some rare items.