[Assessed 87.1%] Detached house in Kawaguchi City, Saitama — 18 min from Hatogaya Sta.

A 36.99 million yen new-build detached house in Oaza Angyojirin, Kawaguchi City, Saitama, an 18-minute walk from Hatogaya Station on the Saitama Railway. Land 65.68 sqm (registry), building 112.06 sqm, wooden three-storey 4LDK, due for completion in October 2026. It is under construction, with handover set for October 2026.

The assessed ratio is 87.1%: 7.55 million yen for the land and 24.65 million yen for the building, 32.21 million yen in total. The inheritance-tax roadside land value for fiscal 2026 is 115,000 yen/sqm (roadside value map 28103). The building is calculated at the wooden replacement unit price of 220,000 yen/sqm over a 22-year statutory life, and being new it carries the full 22 years. The roadside value has risen 9.5% in two years: 105,000 yen in 2024, 110,000 in 2025 and 115,000 in 2026.

Because the address is given as "Oaza Angyojirin", we first checked whether this is a multiplier area in an urbanisation control zone. The listing gives the city planning field as an urbanisation promotion area and the zoning as Category I Residential; multiplier areas carry no zoning designation, so a multiplier area is ruled out.

With no lot number published, we narrowed the position by trilateration. We fitted the six distances to nearby facilities given in the listing (1,440 m to Hatogaya Station, 800 m to Jirin Elementary School, 400 m to the Maruetsu Angyojirin branch, 300 m to Angyo Nursery, 400 m to Midorigaoka Kindergarten and 350 m to Angyojirin South Park) against those facilities' real coordinates from OpenStreetMap. The listed distances are road distances, so we estimated the conversion factor to straight lines at the same time: it converged on a single point at a factor of 0.86 with a 25 m residual. Fixing the factor at 1.0 diverges to a 168 m residual, which also confirms the listed figures are road distances. The Geospatial Information Authority's address API puts that same point within 34 m of the block reference point for lots 46, 120, 61, 41 and 26.

We did not use the coordinates in the listing HTML. The property coordinate field on the athome side is empty and the coordinates in the HTML are the station's. The map coordinates on the other listing put the site 1,794 m from Hatogaya Station in a straight line, contradicting the listed 1,440 m, so we treated them as a rough town point and did not adopt them.

We took 115D as the representative value. The residential streets enclosing this block could be tracked as the same route across all three years: 105D in 2024, 110D in 2025 and 115D in 2026. The band on the Angyojirin part of sheet 28103 runs 95D to 135D, but 95D is a dead-end block and 135D is the arterial value on the prefectural road, so we excluded both. Oaza Angyojirin spans seven sheets and across all of them the band runs 88D to 140D. The ratio comes to 87.1% at 115D, 86.2% at the neighbouring 110D, 83.5% at the lowest 95D on sheet 28103, and even at 88D — the lowest anywhere in the oaza — 82.3%. None falls below 80%. The leasehold ratio symbol is D throughout.

On photographs, the athome listing carries only a floor plan and no site photographs at all (the JSON also flags no photos). We judged this to be an absence in the listing rather than a consequence of the property being under construction, so we looked at other sites — and found the same property on SUUMO, from which we obtained two exterior photographs and two including the frontage road at 1440 px.

The frontage road is a flat asphalt public road and the site is flush with it. The concrete apron on the site side runs right up to the road surface, with only the gutter grating between; the difference is under 0.1 m by eye. We checked the entire perimeter: a wooden louvre fence on the south-east, the neighbouring house directly abutting on the north-west, and on both the ground is level on either side with nothing retained. There is no retaining wall, ashlar or concrete retaining anywhere. The steps up to the entrance are the two courses of the foundation upstand, 0.3 to 0.4 m, under 1 m.

National 5 m laser survey data reads 5.7 m at the site, 5.5 to 6.2 m within a 25 m radius and 5.0 to 6.5 m within 50 m — a gentle gradient totalling about 1.5 m across 100 m, with no metre-scale step. This agrees with the photographs.

Note that the exterior photographs show the building under scaffolding and protective sheeting.

At our 20:00 check on 30 August 2026 the athome listing had been taken down (404). The SUUMO listing of the same property is still live, so we have switched our source to SUUMO. The price, areas and completion date are unchanged.