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Karlo Percinic

Solo founder building LandlordHub — rental management for small self-managing landlords — and BreakWatch, an early-stage monitor that warns you before third-party API deprecations break your product. Zagreb 🇭🇷


Building

Two products, building in public — LandlordHub (live) and BreakWatch (validating).

  1. LandlordHub

    All-in-one rental management for self-managing landlords with a few units — rent tracking, tenant portal, maintenance requests and document storage in one simple app. Not built for agencies. Built for the landlord still running everything in spreadsheets and WhatsApp. Free for your first property, €9/mo for unlimited.

    Live €0/mo
  2. BreakWatch

    BreakWatch watches the changelogs and deprecation notices of the third-party APIs your product depends on (Stripe, LLM providers, payment/auth/email vendors) and alerts you before a breaking change ships — so you fix it on your schedule, not during an outage. Currently in staging, validating with early users.

    Building