$32.88 at Bunnings https://www.bunnings.co.nz/brita-maxtra-pure-performance-fil…
$39.98 at Mitre 10 now, was $32.98 last week. https://www.mitre10.co.nz/shop/brita-maxtra-4-pack-pure-perf…
Use 15% low price guarantee from Mitre 10, making the deal of $27.95
Another cheaper option is the Prestige water jug with filters from Briscoes. The replacement cartridges are $37 for 6 (and of course often on sale so today they are $25.89) or 3 pack at $18.89.
The jug itself retails at $80 but is also on sale at $32 at the moment.
Got a Mitre10 price beat to $28.29, not sure why it was off but couldn't be bothered questioning it over a couple cents.
Bunning's upped their price today Saturday :(
fwiw, Mitre 10 did this 4 pack for $20 on a special in July 2021