Enquiries do not keep office hours
Portal and room-let enquiries arrive at every hour of the week. Whoever replies first tends to win the viewing. A queue that is only worked in the daytime loses the applicants who searched at night.
Operations-as-a-Service for UK lettings agencies
We run your lettings operation, so you can grow without hiring.
Sello is a lettings CRM with the operation already running on top of it. Contacts, applicants, viewings, tenancies and repairs in one place — and the continuous administrative work of letting property handled around them, from standard single-family ASTs to high-turnover room-lets and HMOs. If you already have a CRM you keep it, and Sello extends it instead. Your accounts stay yours either way.
Built room-first: availability, matching and tenancies work per room, not just per property.
The bottleneck
Software has not been your constraint. Capacity has.
Another platform gives your team one more place to type. It does not answer the enquiry that lands at 21:15 on a Sunday, chase the reference that has gone quiet, or notice that a room went void three weeks ago. Those are operational jobs, and they are the ones that quietly cost you a let.
The work is scattered across inboxes
Leads arrive from portals, email, WhatsApp and phone, and each one has to be read, understood and re-typed somewhere before anything can happen. The re-typing is the job that never ends.
Room-lets multiply the admin, not the rent
A single HMO can carry a dozen separate tenancies, deposits and start dates. Mixed portfolios mean tracking per-room availability alongside whole-property lets, and the admin scales faster than the income does.
The division of labour
We run the administrative engine. Your people keep the relationships.
The split is deliberate and it does not move. Repeatable, checkable, high-volume work runs on the engine. Anything that needs judgement, a face, or accountability stays with your team.
Continuous operations
- Property and room records created and kept current, per room
- Listings prepared and published, with photos synced from your own folders
- Every inbound enquiry captured, parsed and written to the record
- A first reply drafted and sent, so no enquiry sits unanswered
- Applicants matched to live stock with an explainable score
- Viewings coordinated into your team's diaries
- Availability tracked per room, not just per property
- Compliance gates checked before anything irreversible happens
Judgement and presence
- Every conversation after the first message
- Viewings, inspections and inventories on the ground
- The referencing decision — always, without exception
- Approving anything irreversible, under role permissions
- Marking a let, and standing behind it
- Landlord relationships and winning new instructions
What is built
The operations we run
Property and room intake
Properties and rooms are created, edited, withdrawn and restored, with photo upload and per-room availability. Withdrawal is reversible; nothing is silently destroyed.
Listings and public pages
If you bring a CRM that already feeds the portals, those feeds stay native to it and we say plainly that we are not in control of them. Either way, every property gets a shareable public page that needs no login.
Lead capture
Enquiries from portals, email and messaging are read, structured and written to the record as they arrive, so the pipeline reflects reality rather than someone's memory.
Matching and scoring
Applicants are scored against live stock and the score is explainable — you can see which criteria produced it. No ranking you cannot interrogate.
Pipeline and assignment
A six-stage lead pipeline with ownership, assignment and audit. Managers can see where every applicant sits and who is accountable for the next move.
Referencing, deposits and payment
The administrative work around referencing, deposit registration and payment is prepared and tracked. The decisions stay human and the money stays in your accounts.
How it works
From enquiry to keys, one tracked path
Every applicant moves through the same six stages, and each transition is recorded with who moved it and why.
- 01Captured
Enquiry arrives
Read from the channel it came in on and written to the record.
- 02Qualified
Matched and scored
Checked against live stock and your criteria, with the reasoning shown.
- 03Contacted
First reply sent
One drafted first message. Every reply after that is your team.
- 04Booked
Viewing coordinated
Placed into the diary of the person who will actually attend.
- 05Referencing
Checks run
Paperwork prepared and chased. The decision is made by a human.
- 06Let
Tenancy set up
Deposit registered and payment taken inside your own accounts.
Boundaries
The rules the system will not break
These are not policies in a contract. They are constraints in the codebase, and no configuration can switch them off.
Your data is yours, and it leaves with you
Your records, your leads, your Stripe, your WhatsApp number, your Google account. Whether your world sits in Sello or in a CRM you brought, it is exportable in full at any time and you do not need our permission or our help to take it. Easy to leave is a design constraint here, not a courtesy.
A CRM you bring is extended, never replaced
If you already run a CRM you are never asked to migrate. We build against a contract rather than against your CRM's quirks, and lifecycle actions that belong in it stay there, performed by a person. If you do not run one, Sello's own is what you get.
AI writes the first message and nothing more
Automation drafts and sends one opening reply so an enquiry is never left cold. It does not hold conversations with your applicants, and it does not make decisions about them.
Compliance gates are hard
Holding-fee caps under the Tenant Fees Act, deposit protection inside thirty days, right-to-rent before any payment link, VAT on receipts. These block the action rather than warn about it, and nobody can override them.
Irreversible actions need a person
Anything that cannot be undone is gated behind a named role and an explicit human approval, recorded against the person who gave it.
Everything is explainable
Every action carries a log of what ran, what it changed and why. There is no step in the operation you cannot open up and read.
Onboarding
You keep operating while we set up
Onboarding is done with you, in phases, and you hold your own credentials throughout. Whatever you are running on now keeps running until the day you decide otherwise.
We learn how you already work
We review your stock, your screening criteria, and the spreadsheets, groups and templates your team already uses. Your process is the specification, including the parts that only exist in someone's head.
Your stock and contacts, loaded
Properties and rooms, landlords, tenants and live tenancies are loaded into Sello — or, if you brought a CRM, connected to it under your own credentials. Messaging and payment links are configured in your accounts, not ours.
The engine starts running
Enquiries begin flowing through capture, matching and first reply. Your team keeps working exactly as before while the queue starts clearing itself.
Dials set to your agency
Matching criteria, message tone, roles and approvals are tuned as configuration. Never as a fork of the codebase — there is one, and everybody runs it.
Nothing is a one-way door. Your records export in full whenever you ask, the accounts stay in your name, and if you stop we revoke our own access and hand you a clean, current set of data.
I built Sello because I kept seeing the same thing: agencies losing lets to response time and paperwork, not to price or to stock. The enquiry that came in on a Sunday. The reference nobody chased. The room that had been empty for three weeks before anyone noticed.
Most of them had no real system at all. A spreadsheet, a WhatsApp group, a portal login and someone's memory. The advice was always to go and buy a CRM first, which meant paying for a filing cabinet and still doing all the work by hand.
So Sello is both halves. The CRM is there — properties and rooms, landlords and tenants, applicants, viewings, tenancies, repairs — and the operation runs on top of it, so the record keeps itself current instead of waiting for someone to update it. If you already have a CRM you keep it and we extend it instead. Either way the data is yours and it exports whenever you ask. I would rather be easy to leave and worth keeping.
Fit
Whether this suits your agency
A good fit
- Room-let and HMO operators running the book on spreadsheets and WhatsApp
- Agencies with a mixed portfolio of rooms, studios and whole properties
- Teams losing enquiries to response time rather than to price
- Operators who want to grow the book without growing the admin team
- Agencies already on a CRM they want to keep, and extend rather than replace
A poor fit
- Anyone looking for self-serve software to configure themselves
- Teams who would rather not delegate administrative work at all
- Agencies whose entire book depends on portal feeds we do not yet run
Questions
Answers on data, CRM and control
Do we have to change our CRM?
Only if you want to. Sello includes a lettings CRM, and for most agencies we work with that is the point — they are running on spreadsheets and a WhatsApp group rather than on a system. If you already have a CRM you keep it: the connector layer is built against a contract rather than a specific vendor, so your existing structures, reports and history keep working untouched.
Who owns the data and the accounts?
You do. Your records, your leads, your Stripe account, your WhatsApp number, your Google Workspace — all in your name, and everything exports in full whenever you ask, without our help. If you brought your own CRM it stays your system of record and Sello never becomes one.
Is this an AI bot talking to my applicants?
No. Automation drafts and sends the first reply so that no enquiry sits unanswered, and it captures and structures what comes in. Every conversation after that first message is your team, and the referencing decision is always a human one.
Do you handle standard ASTs or only HMOs?
Both. The data model carries whole properties, studios and individual rooms as first-class, so a mixed book is normal rather than a special case. Availability is tracked per room where that is what the property is.
What happens if we stop?
You get a full export — properties and rooms, contacts, applicants, tenancies, appointments and the message log — and we revoke our own access and stop the connectors. If you brought your own CRM there is nothing to move back, because nothing was ever moved out. Either way you leave with a complete, current set of your own records.
How is this different from hiring an administrator?
An administrator is capacity you have to recruit, train, cover and replace. Sello is an operating layer that runs the same work continuously, applies the same rules every time, and writes down why it did what it did. Your team is freed for the work that needs a person.
Running something unusual? Per-agency behaviour is configuration, not custom code. If your setup is atypical, that is a conversation about dials.
Next step
Put the administrative work on an engine
A short call to look at how your agency operates today, and whether Sello would take real work off your team.
Book a callPriced against the operation we run for you. Scoped on the call.