Are you talking just the tank?
You will need filtration, heater and lighting. Thats the basics besides gravel, decor and fish.
Do you want a community tank with a lot of variety or just a single tank buster?
This can determine a lot in regard to your filtration.
I have a 120g 60x18x26 that I will move my Midas and Marble Sailfin pleco into. I will add a school of 5 Silver dollars and the will be all It will have.