Planning fallacy
The Sydney Opera House was expected to be completed in 1963. A scaled-down version opened in 1973, a decade later. The original cost was estimated at $7 million, but its delayed completion led to a cost of $102 million.
Garden Palace
The Garden Palace was a large, purpose-built exhibition building constructed to house the Sydney International Exhibition in 1879 in Sydney, Australia. It was designed by James Barnet and constructed by John Young, at a cost of ₤191,800 in only eight months. This was largely due to the importation from England of electric lighting, which enabled work to be carried out around the clock.