My organization would like to create a full fledged style guide that will be applicable to internal & external web sites, print advertising, trade show design, and overall branding. This article lays out the scope we're aiming for, and has links to many great examples style guide PDFs. The goal is to create a style guide comparable to one of these. I'd like to set realistic expectations within my organization for creating this document. So I have a few of questions pertaining to this:

• We don't have design staff. Should we be looking for a design firm or freelancer to come in for a 2-6 month contract, or do we need a longer commitment?
• If we do go with a firm or freelancer, would the pay-scale be comparable to typical design work, or is a style guide a higher order of work?
• How long should it take a pro to create a style guide? To make estimates more concrete, let's say web only, including all custom graphics.
• Any red flags to watch out for? (Compare: a new coder who fails to use css properly would be a red flag.)