Where the money actually goes

You ask for new shoes and get "We'll see" or "Not this month." You've seen your mum tap her card at the supermarket without blinking, so what's the problem? Money is one of those things that looks simple from the outside and gets complicated fast once you see the whole picture.

Here's a rough look behind the curtain. The numbers below are illustrative only. They vary a lot depending on where in New Zealand you live, how big your family is, whether your family rents or owns, and all sorts of other things. Treat them as ballpark, not fact.

What comes in

Say someone earns $70,000 a year. That sounds like a lot. But before it reaches their bank account, tax comes off, plus the ACC levy, and usually KiwiSaver. Roughly speaking, that $70,000 might end up as something like $1,000 a week actually landing in the account. Two adults working full-time might bring home roughly double that. One parent, or one part-time income, can mean a lot less.

What goes out, roughly, each week

• Rent or mortgage. Often the biggest cost. For a family-sized home, rent can easily be roughly $550 to $800 a week, and more in some parts of Auckland or Wellington. Mortgage payments can be similar or higher.
• Groceries. For a family of four, roughly $300 to $400 a week is common, and it's crept up a lot in the last few years.
• Power. Maybe roughly $60 to $100 a week averaged out, more in winter when the heat pump's going.
• Internet. Roughly $20 to $25 a week.
• Phones. Each phone plan might be roughly $8 to $15 a week, and that's before anyone buys a new phone.
• The car. Petrol could be roughly $60 to $100 a week. Then there's insurance, rego, WOF, tyres and repairs, which can add up to a few thousand dollars a year per car.
• Insurance. House or contents, car, sometimes health. Often roughly $50 to $100 a week altogether.
• School costs. Donations, uniforms, stationery, devices, trips, sports fees and camps can be anywhere from a few hundred to a couple of thousand dollars a year per kid.

Add those up and you can see how $2,000 a week coming in can disappear quite fast. Many families have very little left at the end of the week, and some have less than nothing. That's before birthdays, the dentist, a broken fridge, or Christmas.

Why "just buy it" isn't simple

Your parents aren't only thinking about this week. They're thinking about the car rego next month, the school camp in term three, and the fact that the washing machine is making a weird noise. Saying no to $180 shoes might be about protecting money that's already spoken for.

It's also normal for parents not to share every detail. Some feel stressed or even embarrassed about money, and don't want you to worry. So "We'll see" sometimes means "I'm not sure we can, and I don't want to put that on you."

How to talk about money with your parents

• Pick a calm time. Not in the shop, not when a bill's just arrived.
• Ask to understand, not to argue. "What does it cost to run our house? I'm curious." Most parents will be quietly impressed.
• Think about what you can bring. If you really want something, could you save towards part of it, sell something, or do extra jobs?
• Be honest about what matters to you. If it's not really about the shoes but about feeling left out, say that. It's a different conversation.

Your own money

If you've got a part-time job, you'll see tax come off your pay too. It's a good time to learn the basics: set up a savings account, try putting a set amount aside each pay, and notice where your own money goes. Knowing how it works will make a lot of adult life easier.

And if you're ever worried about money at home, it's okay to ask. You don't have to fix it. Sometimes just knowing what's going on is less stressful than guessing.