How to Track Maintenance Costs Per Unit

A small portfolio usually has one unit that costs considerably more to maintain than the others,
and the owner usually has a vague sense of which one it is without being able to demonstrate it.

That vagueness is expensive. It means the recurring problem never gets fixed properly, the rent
never reflects the running cost, and decisions about which property to keep are made on
impressions.

The fix is unglamorous: attribute every cost to a unit at the moment you record it.

Tag at the point of entry

Add one column to however you currently record spending: the unit.

The discipline is tagging when the cost is recorded, not sorting it out later. Retrospective
attribution is slow, and it silently drops the small items — which are usually most of the
total and exactly the ones that reveal a pattern.

Where a cost genuinely covers the whole property — insurance, the roof, the car park — tag it
as common rather than splitting it. Splitting shared costs across units introduces assumptions
that make the per-unit figures less trustworthy, not more.

Keep common and unit-specific apart

Report them as two separate totals.

Common costs tell you what the building costs to own. Unit costs tell you what each tenancy
costs to service. Mixing them produces a per-unit figure that mostly reflects how you chose to
apportion the roof, which is not information.

Compare per unit and per area

Raw totals favour small units. A large unit will naturally consume more.

Divide by floor area as well and look at both. A small unit with a high cost per unit of area is
a much stronger signal than a large unit with a high total — and it is the one most likely to be
invisible in a simple ranking.

Look at three years, not one

A single year is dominated by one-off events. One expensive failure makes an ordinary unit look
terrible.

Three years separates the genuinely expensive unit from the one that had a bad year. That is the
comparison worth acting on, and it is only available if you started tagging before you needed the
answer — which is the argument for starting now rather than when the question arises.

Split reactive from planned

Within each unit, distinguish what broke from what you chose to do.

A unit with high planned spend is one you have been investing in. A unit with high reactive spend
is one that is running you. Those are opposite situations that look identical in a single total,
and they call for opposite responses.

Count your own time

For a small portfolio the owner's time is a real cost and it is never recorded.

You do not need precision. A rough note of hours spent per unit per month, kept for a quarter,
is usually enough to reveal that one tenancy absorbs disproportionate attention — and that is
frequently the same unit that shows up in the cost figures, which turns two soft impressions
into one documented case.

Use it at rent review and at disposal

The per-unit history is the most useful document you have at two moments: when setting a rent,
and when deciding what to sell.

A unit whose maintenance consumes a meaningful share of its income is not earning what the rent
roll suggests. That is not visible from the rent roll and it is obvious from the cost history.

Act on the recurring item

The end point of all this is a decision: the thing that keeps costing money gets fixed properly
rather than patched again.

Patching is always cheaper this month and almost always more expensive across three years. The
per-unit record is what turns that from an assertion into an argument you can actually make to
yourself.