Real Estate GIS: Property Research Use Cases

Introduction

Real estate work involves a great deal of gathering and organizing location information: switching between several websites to research the area around a property, or cutting and pasting paper maps and screenshots into a document.

GIS (geographic information system) can make this work far more efficient. QGIS, an open source GIS software package, has no license fees at all, so anyone can install it and start using it today.

This article uses use cases based on real estate work, such as property research, property management, and area analysis, to show what QGIS can do. It aims to convey the range of situations where QGIS applies rather than detailed steps, so readers who are new to GIS can follow along too.

The real estate industry and geospatial information

The value of real estate is inseparable from its location. Much of the key information about a property, such as the distance from the station, the school district, land price trends, and disaster risk, is “geospatial information” tied to a location.

In recent years, geospatial information has been released as open data at a rapid pace. In 2023, the Ministry of Justice made its registry office map data available free of charge, and in 2024 the Ministry of Land, Infrastructure, Transport and Tourism (MLIT) began operating the “Real Estate Information Library,” which brings together land prices, transaction prices, disaster prevention information, and more. An environment is taking shape in which anyone can use data directly relevant to real estate work for free.

In response to this trend, the Real Estate Transaction Promotion Center introduced examples of using QGIS in its survey report on “real estate digital transformation (DX) using open data,” and MLIT also published how to display Real Estate Information Library API data in QGIS. QGIS is drawing more attention in the real estate industry as well.

The “National Land Numerical Information Download Service,” which publishes basic geospatial information on national land, land, real estate, and urban development, also offers several manuals that use QGIS, including manuals related to real estate.

The value of QGIS in real estate

Geospatial information related to real estate is published by many organizations, including national and local governments and the Ministry of Justice, each in a different format, so collecting the necessary information into one document takes effort.

QGIS lets you display and analyze this location information overlaid on a single map. Three points make QGIS especially useful in real estate.

1. Plenty of free open data is available

Open data directly relevant to real estate work, such as National Land Numerical Information, the Real Estate Information Library, registry office map data, and hazard maps, has been released one set after another in recent years. QGIS has many features and plugins for loading this data, which makes it an ideal platform for using open data.

2. Combine open data with a company's own data

Excel and CSV data with addresses, such as a list of managed properties or past closed deals, can be plotted on a map and analyzed together with open data. General map services cannot freely overlay a company's own data and open data for analysis. The combination of “company data × open data” is a strength unique to GIS software.

3. No cost to adopt

QGIS is open source software, so there is no license fee. Even if you are interested in GIS but expensive software is a high hurdle, you can start small without worrying about cost.

QGIS use cases in real estate

Here are several use cases in real estate.

Use case 1: Creating a map of a property's surroundings

Scenario: You want to create a map of the living environment around a property to attach to sales drawings and customer materials.

For people considering a property, information about the living environment, such as the nearest station, bus stops, school districts, and nearby facilities, is an important factor in deciding whether to buy or rent. With QGIS, you can overlay data published on MLIT's “National Land Numerical Information Download Service,” such as elementary school districts, junior high school districts, railway stations, and bus stops, and combine the information around a property into a single map.

QGIS's analysis functions also make it easy to draw a circle (buffer) such as “the area within a 200 m radius of a bus stop” or to measure the distance from a property to a facility. This shows visually what “X-minute walk from the station” alone cannot convey about the appeal of a property's location.

Use case 2: Visualizing land price and transaction price information

Scenario: You want a bird's-eye view of price levels in an area on a map to support appraisals and acquisition decisions.

The “Real Estate Information Library,” which MLIT has operated since 2024, publishes information such as Land Price Publication data and real estate transaction prices through an API, and QGIS can load it directly.

If you display Land Price Publication point data on a map, you can see the price level of the target area at a glance. Coloring the points by price range also makes area trends easy to read, such as “prices differ between the east and west sides of the station” or “only the land along the arterial road is priced as commercial land.”

Overlaying a company's own closed-deal data and the locations of properties being appraised also helps in preparing well-grounded appraisal documents and proposals for owners. A map based on public data is persuasive and works well as a tool for explaining to customers.

It is also easy to aggregate land prices by area. For example, the following article shows how to aggregate Land Price Publication prices by municipality in Tokyo.

Use case 3: Checking disaster risk information

Scenario: You want to check the disaster risks of properties all at once ahead of the explanation of important matters.

Under the 2020 amendment to the Enforcement Regulations of the Building Lots and Buildings Transaction Business Act, explaining a property's location on a flood hazard map became part of the explanation of important matters. Checking disaster risk is now an essential part of real estate work.

National Land Numerical Information includes disaster prevention data such as assumed flood inundation areas and sediment disaster warning areas. Loading this data in QGIS lets you check the positions of the many properties you handle relative to disaster risk areas, all on one screen.

Services such as the Hazard Map Portal Site let you check disaster risk on a map. However, you have to open it separately for each property and check them one by one, which takes effort. The advantage of GIS is that you can check all managed properties together while keeping the whole portfolio in view. If you also load a property list (such as a CSV) and plot it in one step, you can extract “which properties are inside an assumed inundation area” in bulk as well.

You can also export the map you create as an image, or as a PDF map like the one below using the “print layout feature,” so you can use it as is in documents.

For the explanation of important matters, always check the original sources, such as the latest hazard maps published by the municipality. Checking in QGIS is best used only as preliminary research.

Use case 4: Checking city planning information such as use districts

Scenario: You want to check the use district and building regulations of a site for property research and the explanation of important matters.

Which use district a property is in determines the types of buildings that can be built and the building coverage ratio and floor area ratio, which makes it basic information for property research. Traditionally, this meant opening each local government's city planning map or website separately.

National Land Numerical Information publishes a large amount of data on city planning area divisions, including use districts, area divisions (urbanization promotion areas and urbanization control areas), urban areas, and the guidance areas of location normalization plans. Loading use district data in QGIS lets you check a property's position on a map with use districts color-coded, and you can check areas that span multiple municipalities at once.

City planning data in National Land Numerical Information may not reflect the latest city planning decisions. For the explanation of important matters, always check the original sources, such as city planning maps published by the local government.

Use case 5: Checking lot numbers with registry office map data

Scenario: You want to check the lot number and lot boundaries of a plot of land being traded on a map.

The Ministry of Justice's registry office map data (kozu data) is available free of charge from the G-Spatial Information Center.

Because lot numbers and lot boundaries can be checked overlaid on a basemap or aerial photo, the data serves as reference material for identifying the land being traded and sorting out rights relationships. Combined with the area information map and disaster risk information described above, it is also possible to consolidate the information needed for property research into a single QGIS project.

This article explains in detail how to load registry office map data in QGIS.

Use case 6: Gathering information during on-site surveys

Scenario: You want to record photos and notes on current conditions linked to a map during an on-site property survey.

Property research requires not only desk-based checks but also checking conditions on site. With QField, the mobile app version of QGIS, you can take the QGIS project built in the use cases so far onto a smartphone or tablet and record photos and notes while checking your current location.

Data entered on site can be brought into QGIS as is, which eliminates the double work of “taking notes on paper at the site, then transcribing them into a PC after returning to the office.”

This article explains QField's features and capabilities in detail.

Conclusion

What did you think of these ideas for using QGIS in real estate work?

Creating a property area map, visualizing price levels, checking disaster risk, checking use districts, and checking lot numbers: none of these needs special development or system investment, and all of them can be started with just the free QGIS and published open data.

If you also prepare your property list as GIS data, it becomes a foundation for daily property management and information sharing within the company. Start by overlaying the surrounding data of a property you are interested in on a map.

QGIS LAB publishes beginner articles as learning packages for those who want to start learning QGIS. See these as well.

Data used

• GSI Tiles (Geospatial Information Authority of Japan)
• “National Land Numerical Information (Railway Data)” (MLIT)
• “National Land Numerical Information (Bus Stop Data)” (MLIT)
• “National Land Numerical Information (Assumed Flood Inundation Area Data)” (MLIT)
• “National Land Numerical Information (Land Price Publication Data)” (MLIT)
• “National Land Numerical Information (Elementary School District Data)” (MLIT)
• “National Land Numerical Information (Administrative Area Data)” (MLIT)
• “National Land Numerical Information (Future Population Estimate Data by 250 m Mesh)” (MLIT)
• City Planning Decision GIS Data (MLIT)
• Ministry of Justice Registry Office Map Data