Architect residential extension

Im looking to owner build a house extension based in Perth Australia. looking to get some preliminary drawings drawn up to submit for development approval. I have my old house plans, however the dimensions are tough to read. Seeking a full set of drawings eventually. However progressing through stages, Preliminary/Concept design (floorplan/Site layout/elevations/demolition) progressing to full set of working drawings.

Happy to explore single storey additons/Double storey additions. Hoping to add to the house:
Theatre room
Extended kitchen
Double garage (possible undercroft/double storey on top of addition)
approx 180m2 additional area
Study/Library
new master bedroom with WIR and Ensuite