Aera · First Home Training Camp S.03 · Day 12
Your own budget. Built with AI.
Build a 3-month expense tracker with AI, then fill it in with your real numbers. It's the same 3 months a bank will ask to see. Your deposit is hiding in there somewhere. Let's find it.
The rule
Never paste your bank statements into an AI tool. They show your name, your account number and every transaction you've made. Use the AI to build the empty tracker, then fill it in yourself, privately.
01 · Step 1
Use whichever one you like. They all have a free version.
ChatGPT
Claude
Google Gemini
Microsoft Copilot
02 · Step 2
Copy everything in the box below and paste it into the AI tool.
You are helping a first home buyer in New Zealand or Australia build a simple 3-month expense tracker. Build the empty structure only. Do not ask me for bank statements, account numbers or any personal details. Give me the tracker as tab-separated text in a code block, starting in cell A1, so I can paste it straight into Google Sheets or Excel. Use working formulas, and check that every formula points to the right rows. Use New Zealand dollars unless I tell you I'm in Australia. Layout:
- Column A for categories, then one column for each of the last three months (use the month names), then a 3-month average column, then a "Spike check" column.
- Work out the average as the sum divided by 3, so the empty template shows 0 and not errors.
- On expense rows only, the Spike check shows "Check" if any month is more than 50% above the average.
- Income at the top: take-home pay plus any other income.
- Fixed expenses: the costs I can't really change, such as rent, power, internet, phone, insurance, basic groceries, transport to work, set bills and loan repayments.
- Discretionary expenses: the costs I choose, such as extra groceries and treats, takeaways and delivery, eating out, subscriptions, nights out and alcohol, shopping, travel, buy now pay later and gambling.
- A total for each bucket, month by month.
- What's left over at the bottom: income minus fixed minus discretionary. Below the table, add a short "What a lender looks for" checklist: buy now pay later, gambling, overdrafts or missed payments, and any month where spending spikes, because a lender will look at the last three months of statements. Also remind me not to count transfers to my own savings or KiwiSaver as spending. Keep it simple. When it's ready, ask me if I want to change any categories.
You'll have a working template in seconds. Ask it to change anything you don't like, such as adding a category or renaming one.
03 · Step 3
Log in to your internet banking and export the last 3 months of transactions for every account you spend from. Most NZ banks let you download them as a CSV or spreadsheet file.
Don't fill it in from memory. Memory always underestimates. The real transactions show you where your money actually goes.
04 · Step 4
Copy the tracker into Google Sheets or Excel. Go through your transactions and put each one into Fixed or Discretionary. Do this yourself, not in the AI tool.
05 · Step 5
A lender will, so you should first. Check for:
Then pick the discretionary costs you'll cut. Every dollar you move out of that column goes to your deposit.
Why 3 months?
It's the window a bank asks to see when you apply.
Why 2 columns?
Fixed costs are mostly out of your hands. Discretionary is the money you control. That's where your deposit is hiding.
06 · Lock it in
Aera · First Home Training Camp S.03
Done? Tap Complete on today's action in the app to keep your streak going.