Preliminary Commercial System Design - Feasabilty Study and Design DraftDesign Package includes: Site Plan Layout Single Line Diagram This Cost Effective Preliminary Design is great for early stage deliverables to determine major equipment for the site, system size, and a deliverable to submit for interconnection application or provide to contractors as a bid set. *Note, deliverable does contain enough information to submit to the building department for a permit. Note: cable sizing and stringing are included.