Monitoring selected companies in a portfolio of business tenants.
The question
How do you keep an eye on a portfolio of commercial tenants?
The idea came from a commercial property manager with a substantial portfolio of business tenants.
Certain changes at a tenant company could be worth knowing about.
A new set of annual accounts.
An insolvency signal.
A company becoming inactive.
An address or legal-form change.
The information already existed in the Dutch trade register.
The problem was noticing it.
Checking individual companies manually was possible, but across a larger tenant portfolio it quickly became repetitive and inconsistent.
So the practical question was:
Can the relevant changes simply come to us instead?
The useful moment isn't when someone remembers to check. It's when something changes.
What I built
A lightweight monitor for selected tenant companies.
I built a prototype that follows a selected watchlist of companies in the Dutch trade register.
For each company, the monitor checks a defined set of signals.
When something relevant changes, it sends a short alert through Telegram or email.
The idea is deliberately simple:
monitor the companies that matter, ignore the rest, and notify someone only when there is something worth looking at.
The prototype currently supports signals including:
- new annual accounts
- insolvency signals
- active / inactive status
- address changes
- legal-form changes
- registered business activities
- postal-code region
- company start date
The objective wasn't more data.
It was less manual checking and earlier awareness.
Signals
Monitor what matters.
These are defined public-register changes for companies on the tenant watchlist — not predictions of financial distress.
Alert when new annual accounts are filed for a selected tenant company.
Alert for registered bankruptcy, suspension of payments or debt restructuring signals.
Detect changes in the company's registered operating status.
Alert when the registered address changes.
Track changes such as BV, NV or other legal forms.
Detect changes in registered SBI activities.
Track changes in registered location.
Monitor the registered company start date.
How it works
From tenant list to alert.
The loop is deliberately simple:
- Select the companies — Choose the tenant companies worth following.
- Choose the signals — Decide which company changes are relevant.
- Monitor — The system checks those companies for changes.
- Detect — A relevant change is identified.
- Notify — A short alert reaches the person who needs to know.
watch → detect → notify
No repeated manual checking required.
Current status
Working prototype.
The prototype can monitor a selected portfolio of Dutch companies and generate alerts when defined changes appear.
It was built to answer a practical question:
Can this kind of tenant monitoring be made simple enough to be useful?
The answer is yes.
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Have a similar problem?
Why it mattered
Less checking. Faster knowing.
Monitor the tenant companies that matter instead of repeatedly searching company records manually.
Relevant changes can surface when they happen rather than when someone happens to look.
Put the signal in front of the person who can decide whether it deserves attention.
What I liked about this problem
Very specific. Potentially very useful.
This is exactly the kind of problem I enjoy.
The information already existed.
The business need was clear.
What was missing was a practical connection between the two.
Instead of building a large system, I could test the idea with a relatively small prototype:
select the relevant companies, monitor the right signals and tell someone when something changes.
Sometimes that is enough to find out whether an idea deserves to go further.