Active job

Obtaining building consent foor bathroom renos + simultaneous exterior wall insu

1940's house, likely Rimu timber. We are looking at: -replacing 1 toilet, -installing second toilet (pretty much straight over sewer line, septic tank on property), -replace bath with shower, -relocate sink. -Hot water cylinder to be removed, - gas continuous flow heater to be installed, also will be the first gas installation at site. Gas bottle installation still needed -1 wall to be added. 2x walls of bathroom are exterior, these I want to fit insulation to while the GIB is off, and realise I will need to line with building paper to waterproof. Plumber will be used for plumbing work, however I aim to do the rest myself, need to discuss owner/builder exemption, or whether an LBP can inspect and sign off. Getting a bit bogged down with the building consent process, and am looking for assistance getting my head around it. 3 photos attached, 1 of existing layout, 1 of planned additions, and 1 of real estate photo