What you are actually buying

Japanese apartment ownership divides into the exclusive part, which is your unit, and the common parts, which are everything else: structure, corridors, roof, lifts, pipework, grounds. You own a share of the common parts in proportion to your unit.

Two monthly payments follow. A management charge, which funds day-to-day running, and a repair reserve contribution, which funds major works on a long-term plan. The second one is where the risk lives.

The repair reserve decides the real price

Japanese buildings run major repair cycles, and the reserve is meant to have accumulated enough to pay for them when they arrive.

Frequently it has not. Reserves were often set low when the building was new, because low charges sell units, and raising them later requires the owners to vote for their own costs to increase. Many buildings therefore reach a repair cycle with a shortfall.

When that happens, three things can occur, none of them good for a buyer who has just arrived.

• A one-off levy on every owner
• A sharp increase in the monthly contribution
• The work is deferred, and the building continues to degrade

Ask for the reserve balance and the long-term repair plan together. The question is not how much is in the fund. It is how much is in it compared with what the plan says is coming, and when.

Arrears follow the unit, not the person

This one surprises foreign buyers more than anything else on this page.

Unpaid management and reserve contributions are treated as attaching to the unit. If you buy from an owner who was in arrears, the association can pursue you for the outstanding amount. The debt did not stay with the seller.

So ask, specifically, whether there are arrears on this unit, and get the answer in writing before contract. It should appear in the pre-contract explanation, which is one of the reasons that document matters more than its format suggests.

Ask about arrears across the building too. A building where many owners are behind is a building whose reserve is not accumulating as planned, whatever the stated balance.

Read the minutes

The general meeting minutes for the last few years are the most informative document available about an apartment building, and they are not usually offered.

They record what has been argued about. Water ingress complaints. Failed motions to raise contributions. Disputes with the management company. Proposals for major works that were voted down. Problems with particular units or particular owners.

A sales brochure describes the building as the seller wishes it to be seen. The minutes describe it as the owners actually experience it. Ask for two or three years of them, and have them read.

The rules govern what you may do

The management rules and the associated regulations set what is permitted in the building. Several provisions decide whether your plans are possible at all.

Renovation restrictions catch people repeatedly. Moving a kitchen or a bathroom can be impossible where the drainage runs through common parts, and flooring specifications are often mandated for sound insulation regardless of what you would prefer.

The building's age is a different question here

The structural thresholds of 1981 and 2000 apply to apartment buildings as well, and for a concrete building the practical consequence is different from a house.

You cannot strengthen a concrete building unilaterally. Structural work on common parts requires the association to agree and to fund it, which means an older building's seismic position is a collective problem with a collective timetable, not something you can resolve by spending your own money.

Ask whether a seismic assessment has been carried out, what it found, and what the association decided to do about it. The answer to the third part is often nothing, and that is itself the finding.

What an overseas owner should expect

Ownership brings obligations that assume you are reachable in Japan.

• Notices of general meetings, and voting. You can appoint a proxy, and somebody has to receive the notice first
• Monthly charges, which continue whether or not the unit is occupied
• Association correspondence, in Japanese, by post
• Water leak incidents, which in apartment buildings involve the units above and below and are handled at speed

The rules changed on 1 April 2026, in two ways that matter at a distance. Ordinary decisions at a general meeting can now be taken by a majority of the owners who attend or vote, rather than of all owners, so an owner who does not take part has correspondingly less say over matters such as charge increases. And the law now provides for an owner living outside Japan to appoint an administrator in Japan to deal with matters concerning the unit on their behalf.

That last one is worth anticipating. Leaks between units are among the most common disputes in Japanese apartment buildings, and they are resolved by people who are present. An owner who cannot be reached for two weeks is an owner whose position gets decided without them.

Nine things to obtain before you offer

1. The repair reserve balance
2. The long-term repair plan, and what is next on it
3. Arrears on this unit
4. Arrears across the building
5. Minutes of the last two to three general meetings
6. The management rules, including the lodging and renovation provisions
7. Whether a rise in charges is scheduled or under discussion
8. When the last major works were carried out, and what they covered
9. Whether a seismic assessment exists, and what followed from it

These are ordinary requests. A seller or agent unwilling to supply them has told you something, and what they have told you is worth more than the documents would have been.

The rest of what to check, and which office holds each answer, is in what you must verify yourself before buying. And the registered floor area of a unit is measured differently from the brochure figure, which matters for tax reliefs: that is covered in the land area in the listing is a historical record.