The eTA and a visitor visa are not the same thing. Here is a simple, one-minute way to work out which one your trip to New Zealand actually needs.
Your passport is the foundation of your eTA. Here are the validity rules, the renewal trap that catches travellers out, and the dual-national rule.
The IVL is bundled into your eTA fee. Here is what the International Visitor Conservation and Tourism Levy funds, who pays it and who is exempt.
Just connecting through Auckland on your way somewhere else? You may still need a transit NZeTA. Here is who needs one and the 24-hour airside rule.