20×40 Multi-Family Home Design

I have a south-facing 20 ft × 40 ft urban plot and I’m ready to commission the full engineering design for a three-storey multi-family residence. The key outcome I need is a build-ready package that blends practical space planning with an attractive street-side elevation.

Core requirements
• Three complete floor plans showing efficient circulation, structural wall layout and clearly marked bedrooms and bathrooms on every level.
• A front elevation (and side views if helpful) that optimises light for the south orientation while keeping the façade cost-effective for local construction methods.
• Scaled drawings delivered in both PDF for quick reference and editable CAD (DWG or similar) for my contractor.
• Basic sectional drawings indicating floor-to-floor heights and stair placement so the three levels connect smoothly.

I’m open to your professional input on where to fit living, dining or utility zones, but every floor must anchor at least one self-contained sleeping area with its own bathroom to suit multi-tenant use.

Please share a brief outline of your approach, favoured design tools (AutoCAD, Revit, SketchUp, etc.) and an example of a compact plot solution you’ve created before.