Last tax season I logged 46 hours doing my own bookkeeping across all 9 of my rental units, and when I compared notes with a quote from a local tax accountant (zeirishi), I had saved roughly 380,000 yen. That number sounds great until you realize those 46 hours could have gone into finding my next property or fixing a leaking gutter myself. Fifteen years of running rentals on my own has taught me that the DIY-versus-professional decision isn’t really about which option is cheaper on paper u2014 it’s about what your time is actually worth at your current scale.
I’ve gone back and forth on this more than once, switching from full DIY to a hybrid setup and back again as my portfolio grew from 2 properties to 9. Here’s the real math I use now, broken down so you can run the same comparison for your own situation.
What DIY Bookkeeping Actually Costs
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Software is the obvious line item. I pay about 9,800 yen a year for cloud accounting software, plus another 3,000 yen or so for a receipt-scanning app that saves me from typing every hardware store receipt by hand. That’s under 13,000 yen in direct costs. But the real cost is time: for my 9 properties, I spend about 4 hours a month on routine entry (rent receipts, utility splits, repair invoices) and then a brutal 18-20 hours in January getting everything reconciled for the final return. Multiply 46-50 hours a year by whatever your time is worth, and the true cost of DIY becomes obvious fast. At even a modest 3,000 yen per hour of my own time, that’s 138,000-150,000 yen u2014 not the 13,000 yen the software receipt suggests.
What a Professional Accountant Actually Charges
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When I requested quotes for my 9-unit portfolio, I got three numbers: 280,000 yen, 340,000 yen, and 420,000 yen per year, all depending on how much bookkeeping I’d hand over already organized versus a shoebox of receipts. The lowest quote assumed I’d keep monthly records myself and just needed the final return prepared and filed. The highest assumed the accountant would do everything, including chasing my property management company for missing statements. For a smaller portfolio of 2-3 units, I’ve seen quotes as low as 120,000 yen a year, since the return is simpler and there’s less depreciation schedule work.
The Hidden Costs Nobody Talks About
This is where most comparisons fall short. A cheap accountant quote often excludes things you’ll need anyway:
- Consultation fees for mid-year questions (some charge 5,000-8,000 yen per phone call outside the annual package)
- Amended returns if you made an error the first year doing it yourself u2014 I paid 45,000 yen once to fix a depreciation mistake from my second year as a landlord
- Software subscription costs even when you hire an accountant, since most still want digital records rather than paper
- The opportunity cost of a rejected deduction u2014 my father-in-law lost about 90,000 yen in disallowed repair expenses one year because he filed it himself without knowing the difference between a repair and a capital improvement
On the DIY side, the hidden cost is usually stress and error risk. I once miscategorized a 620,000 yen roof repair as a full expense instead of depreciating it, which triggered a correction notice and about 6 hours of back-and-forth with the tax office to sort out.
Where the Break-Even Point Really Sits
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Based on my own 15 years of tracking this, the crossover tends to land somewhere around 5-6 properties. Below that, DIY bookkeeping usually wins on pure cost, especially if you enjoy spreadsheets and have a fairly simple structure (one mortgage, straightforward rent rolls, no major renovations that year). Above 6-7 properties, especially once you’re running multiple loans with different amortization schedules or you’ve done a large renovation that needs to be depreciated over 27 years, the accountant’s fee starts looking cheap compared to the hours and error risk of doing it alone. At my current 9 properties, I’m past that line, which is part of why I’ve shifted to a hybrid model.
A Hybrid Approach That Splits the Difference
For the last 4 years I’ve done my own monthly bookkeeping using the cloud software, then handed the finished, reconciled numbers to an accountant just for the final review and filing. That combination costs me about 150,000 yen a year for the accountant’s reduced-scope service, plus my 13,000 yen in software, plus roughly 48 hours of my own time on monthly entries rather than the full 50+ hours of doing everything myself. I get the error-checking of a professional set of eyes on my depreciation schedules (which is where I’ve made my worst mistakes) without paying for full-service bookkeeping I don’t need. It’s not the cheapest option on paper, but it’s the one that’s actually saved me money net of the correction I mentioned earlier.
How I Decide Each Year
Every December, before renewing anything, I run through the same four questions: did I do a major renovation this year that changes depreciation, did I add or refinance a property, did last year’s return get flagged or questioned, and has my available time actually gone up or down. If two or more answers point toward complexity, I lean toward more accountant involvement; if things were quiet, I lean DIY. That simple checklist has kept me from over-paying in slow years and under-preparing in complicated ones.
Neither option is universally right u2014 it depends entirely on your portfolio size, how complicated your year was, and what your hours are worth to you. That’s the approach I use across all 9 of my properties, and I reassess it every single tax season rather than assuming last year’s answer still applies.
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