1-Anet A8 is the low cost printer if you want cheap setup for you custom parts
2-Another DIY Arduino self made printer , their are load of videos on youtube available where they teach how to build one easily.
3- Ender if you have a bit knowledge ,with little upgrade you can print like pro ,
PLA - the very first printing material everyone uses.
ABS- if purpose of part is to bear heavy loads and stress
TPU- flexible filament if you want wearable flexible parts.