Storefront Signs

I Am Going Into Business Soon And I Need To Advertise My Brands And Products On A Busy Street To Attract Attention From Passers-by. I Am Shopping Now For A Sign-making Machine And Software And Was Hoping I Could Get Some Advice On Which Machine Would Work Best. I Am Pretty Technical And Have A Graphics Designer Working With Us Now. Since I Am Planning To Make About 30 Signs, I Figured Buying A Machine Would Make Sense, But I'm Lost When It Comes To Which Printer To Use.

A Friend Recommended An HP Color Plotter (DesignJet 650), But I'm Not Sure What To Do.

Thank You For Any Help In Advance.
I Will Need To Make At Least 30 Signs To Start And Then At Least 10 More Per Month.