[Assessed 89.1%] Detached house in Edogawa Ward, Tokyo — 15 min from Mizue Sta.

We took the effective site area as the listed 58.52 sqm (surveyed) less a 3.3 sqm private-road burden, giving 55.22 sqm — SUUMO's land area field conventionally includes the private-road burden. The listing records it as "co-ownership share 3.3 sqm x (1/1)". Our practice is to treat a private-road burden expressed as a fraction as a separate parcel and not deduct it, but one over one means a burden borne alone with no co-owners, so we judged it outside that exception and deducted. Without the deduction the land assesses at 14.92 million yen for a ratio of 94.5%. Either way the figure clears 80%, so the conclusion does not change.

The frontage road is 3.4 m wide to the north-west, under 4 m. The listing says nothing about a setback, but we think an Article 42(2) road is likely. Assuming a 0.3 m centre-line setback and a frontage of about 5 m (estimated from the shape implied by 58.52 sqm of land at 60% coverage giving a ground floor of about 35 sqm), a further 1.5 sqm would come off. That gives an effective site area of 53.72 sqm, a land assessment of 13.70 million yen and a ratio of 86.7% — the most severe stacking we can justify. The 3.3 sqm burden may already represent the setback, in which case deducting both would double-count. Whether a setback is required needs checking with the ward office.

Edogawa 1-chome straddles the junction of four roadside value map sheets (53090, 53091, 53099 and 53100), so we fixed the position by coordinate calibration. The sheets carry no text layer, so we read them as images and geocoded the printed block numbers through the Geospatial Information Authority's address API (blocks 9, 10, 13, 14, 17, 20 and 1 of Edogawa 1-chome). The map coordinates in the listing HTML sit about 33 m from the block 9 reference point. From there it is 316 m in a straight line to Edogawa Elementary School (block 1), consistent with the listed 400 m and five-minute walk (a straight-line to road-distance ratio of 1.26 is reasonable). We placed the property at the boundary between the south-east corner of 53090 and the north-east corner of 53099, around blocks 9 to 14.

The residential streets near the property run a uniform 265D on the 53090 side (the grid of blocks 10, 13, 14 and 17 to 20), and 255D, 275D and 280D on the 53099 side (block 9 and around Edogawa 1-chome South Park). We took the conservative 255D (255,000 yen/sqm) as the representative value. We checked the sensitivity. Across the whole town the band runs 210D to 310D (we do not take the 320C to 340C arterial values along Shinozaki Kaido as representative). The modal 265D gives 92.6% and the lower bound of 235D, excluding outliers, gives 82.1%. Only two roads fall below 80% — a dead-end lane at 210D at the south-eastern edge (block 2, right by the school) and 215D at the western edge — but at those positions the school would be barely 100 m away, contradicting the listed 400 m. For the three-year series we followed the same street on sheet 53099 (the road east of block 9) by eye: 230D in 2024, 240D in 2025 and 255D in 2026. The 265D grid on the 53090 side moved 240D to 250D to 265D on the same trend. The leasehold ratio symbol is D throughout the town.

We obtained and inspected two photographs at high resolution — one including the frontage road and one of the exterior. The north-west frontage road is asphalt and close to level with the site; between road and entrance apron there is a single low concrete step. Cross-checked two ways, against a roughly 200 cm door height and a roughly 90 cm window sill, the step is about 0.15 m and at most 0.2 m. Under 1 m, so neither a frontage step nor stepped access. At the south-east corner of the site there is a concrete-block gate-post wall. Counting the horizontal joints gives six courses, about 1.2 m from the site ground to the top. But retaining height is judged by the difference in ground level either side, not the full height of the wall — and the site side (a concrete apron with a potted plant standing on it) and the neighbour side (grass, with weeds growing from the foot of the wall) are close to level. It retains nothing. The retaining height is under 0.1 m; this is a boundary wall and gate post, not a retaining wall.

There is no slope face, protective sheeting or cut slope. The site fronts the road directly and is not a flagpole plot, so no access-strip deduction is needed. The reddish-brown building to the left has its own walls, roof, downpipes and ridge height with a gap between, so this is not a party-wall row house. For terrain we measured six points nearby with national 1 m laser survey data and confirmed 0.0 to 1.1 m above sea level — essentially flat low-lying Tokyo across about 250 m. A metre-scale step would appear at that resolution; none does. This agrees with the reading from the photographs.