I am certified in TIG & have been doing body work for 60 yrs. I started with
a ox/acet torch welding panels & doing lead work in my Uncle's body shop
I currently own a Miller 200 MIG & a Miller 250 TIG. I own a steet rod shop
where we do frame ups.
I have used all the repair methods as the technology changed.
Flux wire is a poor way of doing metal work period.
If you can not afford to buy a small Miller/Lincoln mig using
argon/co2 try to borrow a unit.
The small 110v units can be bought used for several hundred dollars.
I do not know what the current price is on the bottles, but they can usually be bought with the MIG.