I'm retiring my cheapo arc welder and upgrading to a decent MIG/ flux-core wire feeder and I was wondering how much $$ I'll possibly be spending on gas. After some research, argon and co2 seems to be a good choice for mild steel. I know it depends on how much welding I'll do but can you guys get me thinking in the right $$ ballpark. How much gas do you guys usually go through? Thanks. Romeo 95 turbo SE-R