Building A Custom Made Stage

[J Benj]

I am building a custom made platform for a DJ (that can be interchangeable, so other DJs can use it). I need to know how wide and how long to build the platform. How much space does a DJ need to set up his/her gear? There will be more space below the platform for other performers (like dancers and more). So I am just needing the space for the DJ above the stage on the platform. I know they will need a table for their mixer, computer, cdjs or turntables. What size platform would you need?

Thanks!
J Benj