Around 75-100 dollars.
Depends what kind, there are dozens of different Piranha models. You'll have to be more specific in the future.
60 dollars new. 30 used.
Sadly only around $50.00 if it is the best condition. Piranha's havn't been made in years therefore they are worth little to nothing.
usually around $350 NZD
A used stock Tippman is worth around $80-$100
on average you lose about 3-5 shots worth
Roughly $2-300 depending on the condition
used $10-$40 Brass Eagle is a crappy brand
if you want a piranha as a pet it would cost 50 or 70 dollars