So I'm doing this piece by piece due to free time and costs but for the helmet so far
First attempt using "free" files (i subscribe to a patreon for files in general and this happened to be in there)
I used roughly 1/2 a spool of filament so about $12.50
Attempt 2 using TDK Props' files
From my estimations the helmet plus side attachment should require roughly 1.65 kg of filament which is roughly $45
So before sanding, refinishing and other clean up the helmet is running me about $57.50 + cost of TDK Props' files
**Also for reference I have not looked into buying premade kits. I doing this project this way mostly because I enjoy 3D printing and as a way to work on my skills.