Keep watching the Cargo Hold, the main 501st Legion board, and your local Garrison boards for parts. People are always dumping parts here and there, and you can save a good amount of money doing it that way!!!
I have a good quality ROTJ Boba Fett with pretty high end parts I built many years ago and also have gotten 3 used costumes off other 501sters: A Snowtrooper, A Tusken Raider, A Stormtrooper (missing a helmet, so I bought a helmet kit and built the helmet). Besides the Boba, those other 3 costumes basically came ready to wear so I didn't even have to build them! I have one Aker MR1506 voice amp I share between suits, and one Hyperfirm E-11 I use with both the TK and the TS. I'm living proof from all those guys with their $4,000 Boba Fett costumes.......
-ROTJ Boba Fett
-Snowtrooper
-Tusken Raider w/real Totokia from Fiji with Fort Tusken metal mace end.
-Stormtrooper w/ Hyperfirm E-11 and Aker voice amp.
....... all 4
COMBINED cost me $4,000. Translation: Keep your eyes open for deals. They are out there if you hit them at the right time.
Since this is the Boba Fett board, and people like seeing the breakdown of components, here's my current version of my ROTJ Boba:
Helmet: Fiberglass MS3. Bobamaker rangefinder with lights and Hyperdyne moving rangefinder controller. (Purchased used. Every other part of my costume I painted myself). Just got that this week!
Armor: Fettpride, with Ruffkintoy metal right gauntlet darts and psberetta metal knee darts.
Chest Lights: Fettronics
Shin Tools: Bradley Fett
Jetpack: Bradley Fett with DeanO metal light-up beacon.
Jumpsuit/Vest/Spats: JK2 (company doesn't exist any more)
Neck Seal: TK409
Gloves: Slave 1
Boots: Mark Cheng
Cape: TK409
Braids: Julie (her horsehair Magic of Myth set)
Ammo belt: Sith Camaro (leather) with JK2 saddlebags.
Girth belt: Bought at local tack shop. Cut down and colored, myself.
Blaster: I built using a combination of parts acquired from Fett dad and Ruffkintoy.
Voice amp: Aker MR1506 with upgraded slim headset mic.