dont buy one,
all you can buy for $150 is problems, buy a new phone or somethin, either that or save up...
to buy a complete paintball gun with evrything (gun, air, hopper, mask) youll need at least $250
but....
sigh
if you decide not to take my advice, dont get a pirahna, get a spyder, ther pretty reliable, or a tippman, and get a viewloader hopper, probably electric, 20oz co2
but if you get more money tell me, cause those are piece of sh!t guns