Church Renovation Heating System Design

I'm seeking a detailed engineering design for a heating system for a church renovation project, covering RIBA stages 3 and 4. The system concept includes an Air Source Heat Pump (ASHP), buffer tank, and underfloor heating... (Budget: £1500 - £3000 GBP, Jobs: AutoCAD, CAD/CAM, Design, Engineering, Heating Systems, HVAC, Mechanical Engineering, Project Management)