I Used Spreadsheets to Track Rent on My NZ Rental for Years. Here's Why I Stopped.

I'm a software engineer by trade. In some of my early jobs they called me the King of Excel. If anyone should be able to make a spreadsheet work for tracking rent, it's me. And for years, I did make them work. Then I gave up and built software instead. Here is why.

I should have been the spreadsheet guy

I want to be upfront about my bias here. I'm comfortable in a spreadsheet, and for a long time I assumed the problem was that I hadn't built a good enough one. I'd tried Quicken and Peachtree back when I had a property in the US, proper accounting software, but way too complex for tracking a rental. So when I started letting in NZ, I went back to basics: Excel first, then GnuCash for a while, then back to spreadsheets.

Across four apartments in central Auckland - including a three-bedroom apartment and smaller units - I tracked rent from multiple rooms at different rates, partial payments, late payments, car parks, all in a series of tabs and formulas. It worked. Until it didn't.

Three rooms, three rates, one spreadsheet

I rent rooms individually in a three-bedroom unit. Room one at $320 a week. Room two at $240. Room three at $200. Plus a car park at $60. That's $820 a week total, coming from three different people into my bank account at different times, in different amounts.

Every week I'd scan internet banking and try to match each payment to a room. Tenant A usually paid on Monday. Tenant B paid fortnightly. Tenant C paid whenever they felt like it. I had a spreadsheet with a tab for each room, colour-coded: green for paid, yellow for partial, red for overdue. It looked professional. I was a bit proud of it. But maintaining it took fifteen to twenty minutes every Sunday, and that was on a good week.

What did the spreadsheet miss?

The thing about spreadsheets is that they only know what you tell them. They don't watch your bank account. They don't flag anomalies. They just sit there, waiting for you to type in the next row. Here's what slipped through on me:

• Partial payments I didn't chase. A tenant pays $200 instead of $240. I note it, intending to follow up. Next week they pay $240. Both entries recorded. But I'm still $40 short, buried in a column I'd only notice if I checked carefully. That made it harder to see what remained outstanding until I reviewed the ledger.
• Late payments that became a pattern. One tenant was consistently two or three days late. Not enough for alarm bells any given week. But those few days stretched to a week, then two. By the time I realised, they were significantly behind. The rules on overdue rent all turn on being able to show exactly what was owed and when, and my spreadsheet could not do that on demand.
• Rent increases that didn't stick. I sent the 60-day notice, the date came and went, the tenant kept paying the old amount. Took me three weeks to notice because the payment still showed up as a regular deposit, just $20 less than it should have been.
• Room turnover chaos. Tenant moves out, new one moves in at a different rate. Update formulas, adjust expected amounts, carry over balances correctly. Every room change was twenty minutes of careful spreadsheet surgery.

One quick correction while I'm here: the rent-increase notice period in NZ is 60 days, not 90. I get that wrong in conversation all the time. The 90 days is the no-cause periodic termination notice, a different thing entirely. If you're working out what to charge a new room in the first place, our guide to what market rent means in NZ is the place to start.

What can records and software not tell you?

A ledger can show recorded payments and tenancy details, but it cannot inspect a property, confirm who is living there, or resolve a disagreement. Those tasks need clear communication, appropriate visits, and decisions by the landlord. Software can help keep a timeline and make information easier to review; it cannot replace the physical checks or human judgement a situation may require.

For shared homes, agree in writing who the tenants are, how rent is paid, and how changes will be handled. Check the agreement and current tenancy guidance before acting. A spreadsheet or property tool can help organize the records, but it does not verify what is happening inside a home.

Why was tax time the worst?

At the end of the financial year, I needed total rental income per property for my accountant. Sounds simple. It wasn't. I had to go tab by tab, summing actual payments for each room, accounting for partial payments and mid-year rent changes. If the spreadsheet had gaps, and it always had weeks where I'd been busy or on holiday, I'd have to reconstruct from bank statements. Cross-referencing three months of transactions at 10pm the night before the tax deadline is not how I want to spend my evenings.

The law is not vague about this. Section 30 of the Residential Tenancies Act 1986 requires landlords to keep proper records showing rent paid. Separately, Inland Revenue says rental property records must generally be kept for at least seven years for tax purposes. Under-reporting rental income is a compliance issue. Over-reporting means you pay tax you don't owe. Getting the figure exactly right from a manually maintained spreadsheet across multiple rooms was hard. If you want the wider habit rather than just the rent figure, I wrote up the whole system in landlord record keeping in NZ.

Preparing records for a tenancy discussion

When a rent balance needs explaining, a clear timeline can help: the rent due for each period, payments received, and any adjustments. I used to assemble that information from spreadsheets and bank statements, then check the totals carefully. A record or schedule can support a discussion, but it is not a guarantee of an outcome in a Tribunal or a substitute for evidence and advice.

What's the real cost of "free"?

A spreadsheet has no subscription fee, and for a simple rental it may be all you need. As records grow more complex, the trade-off can be the time you spend entering, checking, and summarising them. That cost depends on your own process and should not be assumed to exceed the price of software. Compare your actual workload with the plan price and try the workflow before switching.

From spreadsheets to GnuCash to building my own

I tried GnuCash for a while. Solid software: double-entry bookkeeping, proper reconciliation. But it's built for general accounting, not rental management. It doesn't know what a tenancy is. It doesn't know that $240 on a Tuesday is Room 2's rent, or that it was due Monday. I was still doing all the matching in my head. GnuCash was just a fancier place to record the result.

That's when I started building RentManager. Not because I wanted to build software, I do that all day at work, but because nothing understood my specific problem: multiple rooms at different rates, bank transactions needing matching to tenancies, arrears tracking per period, and tax reports from actual matched payments.

How RentManager handles this

RentManager stores effective-dated rent schedules and calculates rent balances by period from the schedule and recorded payments. You can import bank transactions and review suggested matches; ambiguous or unmatched items need your attention. Partial payments and remaining balances are shown against the relevant periods. You can inspect and export the resulting records, then check them before relying on them in a discussion or application. The software organizes information; it does not guarantee that source data is complete or that a Tribunal will accept a claim.

If you spend time reconciling rent records, see whether RentManager fits your process. Open the live demo to inspect the rent ledger, or start a free trial. Check current plans and pricing before choosing a plan.

Common questions

What's the best way to track rent payments as a NZ landlord? For one property with one reliable tenant, a simple spreadsheet is fine. If you have multiple rent schedules or want less manual record entry, compare a purpose-built ledger with your current process. Imports and suggested matches still need review, and year-end figures should be checked against source records.

Do I legally have to keep rent records in NZ? Yes. Section 30 of the Residential Tenancies Act 1986 requires landlords to keep proper records showing rent paid. Separately, Inland Revenue says rental property records must generally be kept for at least seven years for tax purposes. See Inland Revenue's record-keeping guidance.

How much notice do I give for a rent increase? 60 days' written notice for a residential tenancy (28 days for a boarding house), and rent can only be increased once every 12 months. It is not 90 days, that's the no-cause periodic termination notice, which is a different rule.

Can RentManager handle rooms rented at different rates? Yes. Each room can have its own effective-dated rent schedule. Bank transaction matching can be automatic for higher-confidence matches or suggested for your review; partial payments are tracked by period.