OpenAI Software / SaaS Europe & UK

Scout24

Marketing Personalization

Scout24 needed to move beyond keyword real-estate search so seekers could get guided help, listings, and recommendations that better reflected how people actually explore where and how they want to live.

GPT‑5 powers Scout24’s conversational search assistant HeyImmo

Reported impact

Business outcome

Scout24 launched a more intelligent real-estate search experience, established rigorous AI quality controls for customer-facing answers, and created a platform it can extend across seekers, homeowners, landlords, and agents.

  • Customer Experience
  • Productivity Improvement
  • Revenue Growth

Solution

Scout24 used GPT-5 to build HeyImmo, a conversational real-estate assistant that turns property search into an interactive guidance experience. Rather than only returning results, the assistant can ask clarifying questions, surface relevant listings, summarize options, and adapt its response format to match what a user needs at that moment—bullet points, full explanations, or direct listing suggestions with image previews. The team intentionally simplified its technical architecture away from a more complex multi-agent plan and instead leaned on function calling and tightly scoped components so it could ship, learn, and optimize for latency and reliability. To protect quality, Scout24 built its own evaluation system inspired by the OpenAI Evals framework and delayed launch once to make sure the experience met its internal bar. Broad employee “swarm testing,” close collaboration with OpenAI solutions architects, and a willingness to refine answer structure and edge-case handling helped turn conversational property search into a trustworthy core product experience.

Data flow

User search intent enters HeyImmo, which asks follow-up questions, formats results appropriately, and returns listings or summaries based on GPT-5 reasoning. Quality signals from custom evals and broad internal testing then feed back into answer refinement before new improvements are shipped.

Solution architecture

2 components · 2 layers
  1. Compute
    • GPT-5 Provides the reasoning engine behind conversational search, clarifying questions, and adaptive answer formats.
  2. Serving
    • HeyImmo Acts as the conversational real-estate assistant that guides users through search and listing discovery.

Architecture clues

  • Almost all employees were invited into “swarm testing” to stress-test edge cases
  • Custom quality framework is inspired by OpenAI Evals
  • Launch was delayed once to meet the defined quality bar
  • Team simplified from a multi-agent concept to function calling and focused components

Evidence from the source

"GPT‑5 powering Scout24’s conversational search assistant HeyImmo"
"The company delayed launch once to ensure the experience met the bar"
"We needed a real-estate expert assistant—a sparring partner"
"the team intentionally simplified: using function calling and focused components"
Transparency Evidence & methodology 71/100 reference value · 85% confidence · 1 source

Review how this reference was scored and trace each normalized claim back to its documented source.

01

Scoring methodology

How scores are calculated

Customer Reference Value measures usefulness as a customer reference. Evidence Confidence measures the quality and traceability of available evidence, not independent verification.

Customer reference value71/100
  • Problem clarity20/20
    Measures whether the customer's operational problem is specific enough to compare.
  • Implementation depth25/25
    Rewards named components, data flow, integrations, and architecture detail.
  • Outcome specificity16/20
    Measures whether the reported benefit is concrete rather than a generic claim.
  • Quantified impact0/25
    0 metrics describe measurable impact.
  • Deployment scale10/10
    Rewards evidence of a live or scaled deployment and meaningful integration scope.
Evidence confidence85%
  • Source authority20/25
    The main evidence is an official vendor-published customer story.
  • Claim traceability21/25
    10 of 12 key fields link to a named source.
  • Direct evidence20/20
    4 direct source quotes retained.
  • Date provenance8/10
    The publication date comes from publisher-controlled metadata.
  • Source transparency8/10
    1 source reference document publisher, URL, authority, retrieval, and supported fields.
  • Implementation specificity8/10
    Rewards source-backed components, data flow, quantified impact, and a specific outcome.
02

Traceability

Sources & provenance

Field coverage shows which facts each source supports. Dates are shown only when documented by the source.

  1. OpenAI

    Scout24 customer story

    First-party
    https://openai.com/index/scout24/
    Source type
    Vendor-published customer story
    Published
    Dec 9, 2025
    Supports
    • Customer
    • Business problem
    • Solution
    • Products
    • Solution components
    • Data flow
    • Integrations
    • technical area
    • use case category
    • Business outcome
    • outcome category
    • Metrics
    • Architecture
    • evidence quotes
    • Publication date

Date evidence

Not separately sourced Industry, Region, Company size. Treat these normalized attributes as lower-confidence until a dedicated source is added.