FWIW, our bathroom for our place in Chadstone looks similar to yours and we did a recent renovation:
1. Asbestos Testing $200 (less than 1 day)
2. Self demolishing bathtub/shower/vanity unit and walls (3 days) $0 DIY.
3. Replumbing works $800 INC GST (1 day)
4. Waterproofing and...