Use the tools yourself. Or hand over the brief.
One workspace for buying and holding homes at scale: find and value the homes that fit, underwrite them, plan a programme against your mandate and watch the homes you hold. Every plan includes all of it, and the same allowance pays for the work you do yourself and the briefs you hand over.

Real Viiyoo screen from a demo organisation. Addresses are replaced with descriptions.
Six jobs, one workspace.
What you hold, what you buy next and why you bought it live in one place, so each decision starts from the last one.
Know your book
Import the portfolio you hold, benchmark every home against market, LHA and your mandate, and model what-ifs.
02 · PlanDeploy to a mandate
Write or upload the mandate. Get a screened, underwritten, stress-tested plan and a committee pack.
03 · FindSearch and scout
Live homes across Great Britain on a map, by strategy or in a sentence, with scouts that keep watching.
04 · ValueValue and underwrite
Calibrated values, rents from comparable lettings, the right stamp duty for each nation, and the area behind it.
05 · DecideRecord the decision
A decision drafted on pinned evidence, frozen with its pack and signed off by a second person.
06 · WatchKeep watch
Sales, certificates, planning, ownership and rule breaches on the homes you hold, as alerts and webhooks.
Find
- Search and map across the main property portals, with duplicates removed
- Saved searches
- Scouts that rank new matches and email a digest
Analyse
- Valuations from comparable sales, with a range and confidence
- Rent assessments from comparable lettings and the LHA
- Full underwriting: cash flow, stamp duty, lender stress test, grants such as LAHF and SHAP
- Works costing; condition, auction and dispute flags
Market intelligence
- Tables and maps by region, council, ward and postcode district
- Trends, supply, selling speed and rent-to-income
- Scenario modeller
- CSV and PDF export, saved views
Mandates and engagements
- Write a mandate, the rules, in plain words or a form
- Acquisition screens, value-add appraisals, deployment plans and portfolio rent reviews
- Standing briefs that report what changed since the last release
- Your own person reviews and releases
Portfolios
- Holdings
- Rent monitoring against the market and the LHA
Outputs
- Packs, workbooks and CSVs in your own branding
- Every figure traceable to its source
- A decision log and a full audit trail
Ways in
- The web app
- The Claude and ChatGPT connectors
- Single sign-on and SCIM
Service
- Your methodology profile set up and calibrated at onboarding
- A named support contact
- Client data held in the UK
The screens, as they are today.
Every tool an engagement uses is yours to run, and your own AI agents can work from the same evidence through the Claude and ChatGPT connectors and a versioned API. For agents and developers.





Real screens from a demo organisation. Addresses are replaced with descriptions.
Every figure tells you how sure it is.
Every value comes with a range and a confidence level, doubt is flagged rather than hidden, and no figure comes from AI. We test it all on homes that have sold, and publish the result.
median difference from the price paid where confidence is high
sale prices fell inside the range Viiyoo gave
median difference from the price paid, across every confidence level
average bias: Viiyoo values neither high nor low
Homes valued as they stood on the day they sold: 290 sales across 40 postcode districts in England and Wales, July 2025 to June 2026. Measured 28 September 2026.
Ready for the people who check the work.
Secure by default
Single sign-on through your identity provider with SCIM, or authenticator-app sign-in; visible sessions and an audit log owners can read.
Decisions with a second signature
A decision is frozen with its evidence pack and signed off by a second person. No API can sign one off.
Your brand on the work
Reports and emails carry your organisation's name and colours, powered by Viiyoo.
Books of real size
Portfolios of up to 20,000 homes; 10,000 assessed in about 80 minutes.
What is on the way.
Designed or being built, and not yet switched on. We label it rather than blur the line, and it joins every plan when it is live.
- Market forecastsPrices and rents 3, 6 and 12 months ahead, with an upside and a downside, withheld where the evidence is thin, and their accuracy published. The method is agreed; it is being built.
- Neighbourhood rulesSchools, GPs, crime, lease length and what a listing says about access, as rules a mandate can use. Being designed.
- Listings with no house number, valued as a typical homeSo the last listings that cannot be placed on one home can still be screened. Being built.
- Viiyoo in the Claude and ChatGPT directoriesThe connectors work today as custom connectors; directory listings are on the way.
Viiyoo is made by Proanex Ltd
A UK technology company registered in England and Wales (company number 17461523). Built on open and official UK property records.
See it on your own patch.
Access is by invitation today. Talk to us and we will show you the work on the homes and areas you know, before you decide.