i suggest if you are just going to budget costume, don't costume
go to halloween express. no point in even having a good helmet and everything else be sub-par. even if you made everything from scratch your materials are going to be at least $100. and then time making stuff is worth something ( i hope )
given
goodwill shoes to conver to boots ($2.99-6.99)
fabric for vest, jumpsuit, cape, neckseal, spats, pouches, belt ($15-40)depending on what you get, if it's on sale etc.)
bits and pieces for gun, toy gun, pvc pipe, metal ($4.99-9.99)
plastic for helmet, armor, jet pack etc. ($15-20)
paint: black, grey, green, blue, orange/yellow, silver, red/maroon ($30-40)
and who knows how far that basic stuff will even get you
-=QuinN!