Armin Sanjari
Managing Director, mathematics and analytics
Founded the agency IT-WINGS in 2016 and still runs it. It serves well-known clients in the automotive, consumer goods, pharma and mechanical engineering industries.
Propspector.AI software for real estate files.
We built Propspector and we run it ourselves. The software reads the documents on an apartment or house against a fixed review catalog, from the land register to the building file. The report shows every deviation with its source reference. It also includes a market value estimate via an external API.
First the facts. Then the cross-check.
Propspector checks each detail on its own, then each one against all the others. Click through an example (the demo is in German).
Befunde aus dem Abgleich
- Wohnfläche weicht erheblich ab
Das Exposé gibt 48,12 m² an, die Wohnflächenberechnung weist 41,55 m² nach WoFlV aus. Eine Abweichung von 15,8 %.
- Grundriss erfüllt Bankanforderungen nicht
Dem Grundriss fehlen Maße, ein Maßstab und die eindeutige Objektzuordnung. Das Dokument ist in dieser Form nicht für eine Finanzierungsprüfung geeignet.
- Teilungserklärung unvollständig
Im Grundbuchauszug sind Nachträge vom 12.02.1992 und 19.03.1992 vermerkt. Diese fehlen in den vorliegenden Unterlagen der Teilungserklärung.
Was die Finanzierung noch braucht
- Aufteilungsplan
- Fehlt
- Nachträge zur Teilungserklärung (1992)
- Fehlen
- Aktueller Grundbuchauszug
- Veraltet (2019)
22 files in. Sorted file out.
Documents arrive unsorted and badly named. Propspector identifies the documents, assigns them to the right part of the report, cross-checks them and flags what is missing.
- IMG_2231.HEIC: identified as Floor plan
- Baugesuch 13.11.1975.pdf: identified as Building permit
- Scan 14.01.2026, 09-42.pdf: identified as Declaration of division
- energieausweis_final(2).pdf: identified as Energy certificate
- 2871_WOHNUNG_FINAL_v3.PDF: identified as Land register extract
- baubeschreibung_scan.pdf: identified as Building specification
- Protokoll ETV Juli (Kopie): identified as Owners’ meeting 2025
- Auszug_Baulasten_2019.pdf: identified as Public easements register
- Einzelabrechnung_final.pdf: identified as Annual statement 2024
- IMG_4471.jpg: identified as Chimney sweep certificate
- umlaufbeschluss24 (2).pdf: identified as Circular resolution 2024
Three special levies. Pulled from all the minutes.
Propspector reads the minutes of every meeting and every circular resolution, tracks topics across the years and collects all approved special levies in one place. It also catches a missing year of minutes.
- Balcony and facade renovation (2025)165.000,00 €
- Special levy for replacing the elevator control system (2024)27.000,00 €
- Skylight repair / replacement (2024)10.000,00 €
Findings are sorted into “clarify before purchase,” note and no issues. Each one names the document and the page it comes from. The report runs in the browser and on a phone and also comes as a PDF.
The model reads. The code decides.
A single AI pass misses things or invents them. That’s why Propspector works as a chain of specialized reviewers. The language model pulls the printed facts out of the documents. Hard-coded logic handles the calculating, comparing and classifying.
Review individually
Each document type has its own reviewer with a fixed catalog. The model extracts the facts, each with its source reference.
White label.The report under your own brand.
Appraisal firms and advisors pass the report on to their clients under their own name. So we built an editor right into the report.
- Custom logo on the PDF
- Every report carries the firm’s logo and details. Propspector doesn’t appear in it.
- In-report editing
- Any text can be clicked and edited directly on the page.
- Custom ratings
- Findings can be upgraded or downgraded. The original stays visible and can be restored with one click.
- Custom findings
- New findings and a chapter on the site visit are added before the report goes to the client.
The “Customize PDF” editor with sample data. Click to start the video.
Other systems upload. Propspector reviews.
Third-party software creates the property and uploads the documents. The finished report comes back as structured data and as a PDF. AI assistants access it directly via MCP. We currently offer the API and MCP as a pilot, on request.
REST-API
- POST/propertiesCreate property
- POST/properties/{id}/documentsUpload documents
- POST/properties/{id}/analysisStart review
- GET/properties/{id}/reportRetrieve the report as JSON and PDF
MCP for Claude and ChatGPTExample
What needs to be clarified before buying at Beispielweg 8?
get_report_summary
Three points. According to the building permit, the attic doesn’t count as living space, the energy source differs from the building file, and the plot size doesn’t match the land register.
- list_properties
- get_property
- get_report_summary
- get_report_chapter
- get_account
- get_upload_link
- create_property
- start_analysis
Eight tools. Starting a review is marked as a modifying action. Before it uses credit, the assistant checks with you.
Built with people who read files like these.
We have been working on Propspector for almost two years. We developed the review catalog with appraisers, financing advisors and real estate dealers. Every case that shows something new helps us refine it.
Anyone who processes other people’s purchase documents is responsible for their data. That’s why data protection is built into our architecture.
- Hosting in Germany
- The application and storage run on servers in Germany. That’s where the uploaded documents are stored and where the report is created.
- Processing in Europe
- The AI analysis also runs in an EU region. No data leaves Europe.
- No training on customer data
- Documents, inputs and reports aren’t used to train AI models.
- Data processing agreement under Art. 28 GDPR
- Anyone who uses Propspector for their own clients remains the controller. The agreement is publicly available.
- Deletion on request
- On request, we enable automatic deletion of the documents after 30 days.
The people behind it.
More about us
David Otto
Managing Director, economics and growth
Has been scaling digital businesses since 2015, first at Festool, then for six years at Mercedes-Benz. There he led projects in digital products and global performance marketing.
Common questions about Propspector.
Something like this for your documentsWhat is Propspector?
Propspector is a software product by Kessel & Code. Using AI, it reads the purchase documents for apartments and houses against a fixed review catalog and produces a report that lists every deviation with its source reference.
Who is Propspector for?
For anyone who reviews real estate files, such as appraisers, mortgage advisors and investors. Private buyers also use it before buying. Details and pricing are on propspector.de.
Does Propspector replace an appraiser?
No. The report isn’t a market value appraisal or legal advice. Propspector does the reading and comparing. The on-site assessment and the professional decision stay with people.
How is this different from a normal AI chat?
A chat answers freely. Propspector follows a fixed review catalog. The model extracts the facts from the documents, and deterministic code handles the comparisons and classifications. Every finding points to its source.
Does the data stay in Europe?
Yes. The application and documents sit on servers in Germany, and the AI analysis runs in an EU region. Business customers get a data processing agreement under Art. 28 GDPR.
What is the MCP interface?
MCP (Model Context Protocol) is an open standard that lets AI assistants such as Claude and ChatGPT access software. With the Propspector MCP server, you ask your assistant about properties and reports. Before a review uses credit, the assistant checks with you.
Is there an API?
Yes, as a pilot, on request. Your software creates a property, uploads the documents and gets the report back as JSON and PDF. It’s the same review as in the app.
Can you build something like this for our documents too?
Yes. The same approach works for contracts, minutes or technical documents. We then build the review catalog with your specialists.
Want something like this for your company?
We use the same approach for your documents and processes. Tell us briefly what you need. You’ll get an answer within 24 hours.
hello@kessel-und-code.de
Rotebühlplatz 11–15, 70178 Stuttgart