Ninety-six apartments, one record for each.

The company manages a residential building and wanted to stop running it from a spreadsheet. Units, tenancies, post-dated cheques, ownership shares, maintenance requests and contractor jobs were spread across a workbook, WhatsApp and memory.

They needed one system the office team uses every day, with a portal for each outside party: tenants raising requests and seeing payments, owners seeing dashboards and reports, contractors receiving and closing jobs, and technicians working on site.

The data was real and imperfect. The client’s workbook had units that did not match, ownership shares that did not add up to 100% and amenities recorded as free text. Importing it as-is would have put those errors straight into the new system.

Technicians work in plant rooms and basements on a weak signal, so their app had to fail honestly: a dropped connection shows a clear error, never a false “saved”. And every reference number — tenancies, parties, work orders — had to stay unique and sequential however many people were entering data at once.

We built to the client’s actual portfolio from the first week instead of to a prototype. A workbook import checks every row and lists the problems — mismatched units, broken ownership splits — for the office to fix before anything is committed.

Reference numbers are issued by the database itself, so they cannot collide. Notifications go out through an outbox, which means a message is only sent once the change it describes has been saved. Every write carries an idempotency key, so a retry after a dropped connection never creates a duplicate. Every screen shows the same record to each role, limited to that role’s part of it.