Do partially-thrifted costumes count? I saved a bunch of money on my and my younger brother's costumes last month. In this photo, I'm in the Katara costume on the far right, and he's in the "Bolin" costume right next to me. http://www.cosplay.com/gallery/a320575/
Katara: I made the robe myself, but aside from that:
- the pants were a $5 find at a thrift store, and I altered them slightly
- the shoes were already owned by me. They were darker than the characters shoes, but they had the right shape, as well as a neat swirl-graphic on the top that was reminiscent of water, which fans of the character took notice of, and loved!
- instead of buying her water pouch, I knew I needed a bag to carry things at the con anyway so I used a purse that was the right shade of brown, as well as the perfect shoulder strap. People knew right away that it represented her water pouch
I don't know how much the bag cost as it was a gift from years ago.
The entire costume, minus what was preowned, only cost me about $30.
Bolin- bought the jacket online ($60) due to time constraints
- the undershirt was a turtleneck that was too small for him. I cut it up and trimmed it with scrap fabric to make an oriental neckline.
- the pants were the bottom of his old karate gi that were also too small for him. I altered them to look like knickerbockers.
- the spats were simply an old pair of thigh-high socks I altered.
- the shoes were pre owned.
- the sash was made from scrap fabric
Aside from the shoes, this would have cost about $130-$150 if it was all purchased new. By altering pre-owned items, my only actual expense was the $60 jacket.
I hope that helps!