Legally split heat pump costs with tenants and maximize subsidies
German homeowners and tenants face massive financial uncertainty from either high upfront heat pump costs or rapidly rising gas/oil heating expenses (projected to double by 2040) due to shifting regulations and green fuel mandates.
MietUmlage helps landlords calculate the exact legally recoverable portion of heating modernization costs according to German tenancy law (GEG + BGB §559). It generates compliant tenant letters, tracks consents, optimizes subsidy allocation between parties, and produces tax documentation.
German homeowners, landlords, and tenants in residential buildings facing heating system replacement decisions
Embedded up-to-date legal database of court rulings and exact umlage percentages for heating systems — updated monthly by a legal partner.
professional
Upload or enter multi-unit building and tenant data
Automatically computes maximum recoverable amount per tenant per German law
Creates tenant notification letters, consent forms and rent increase notices
Shows how to divide grants between landlord and tenants for best tax outcome
Track which tenants have agreed and when rent increases can take effect
Generates documentation for landlord tax return
Alerts for legal deadlines (e.g. 3-month objection period)
Secure link for tenants to view and digitally sign documents
View impact across entire property portfolio
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| text | No | |
| role | text | No |
| created_at | timestamp | No |
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| user_id | uuid | No |
| address | text | No |
| unit_count | int | No |
| postcode | text | No |
Relationships:
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| building_id | uuid | No |
| total_cost | int | No |
| system_type | text | No |
| status | text | No |
| created_at | timestamp | No |
Relationships:
| Column | Type | Nullable |
|---|---|---|
| id | uuid | No |
| building_id | uuid | No |
| unit_number | text | No |
| text | Yes | |
| consent_status | text | No |
Relationships:
/api/calculate-umlageRun legal cost allocation calculation
/api/documents/generateGenerate PDF tenant letters
/api/consents/updateUpdate tenant consent status
/api/buildingsFetch portfolio overview
1 modernization project
None
Unlimited
| Month | Users | Conversion | MRR | ARR |
|---|---|---|---|---|
| Month 1 | 85 | 14% | $406 | $4,872 |
| Month 6 | 620 | 22% | $3,814 | $45,768 |
Automatic umlage calculations, compliant letters and consent tracking — built for German landlords.
1. Partner with two regional Haus & Grund chapters offering free 3-month Pro accounts to their members for case studies. 2. Post detailed guides in Immobilienscout24 landlord forums with link to tool. 3. Run LinkedIn ads targeting 'Immobilienverwalter' and 'Vermieter' job titles in Germany with a free umlage calculator lead magnet.
Strong legal reputation
Generic templates, no automated calculation engine
Instant precise calculations specific to heating upgrades
Large user base
No specialized heating law logic
Deep focus on GEG modernization cost allocation
Curated legal ruleset updated monthly with new court decisions, creating a data asset competitors cannot replicate quickly
The combination of mandatory heating replacement deadlines and the complex 2024 GEG tenancy cost rules has created massive confusion and risk for landlords right now.
Incorrect legal output leads to landlord lawsuits
Strong disclaimers, templates reviewed by actual German tenancy lawyer, 'for information only' language
Keeping legal database current is time-consuming
Build simple admin CMS and budget €400/month for legal freelancer
Success: At least 70% indicate they would pay for automated legal tool
Success: ≥90% accuracy reported and 25% conversion
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