
From a philosophy degree and a decade in customer care to AppFolio's C-suite, Horner has built a career around one durable idea: good marketing begins by being useful.
Propexo is a Boston-based proptech startup building the unified API and data platform for multifamily real estate. Often described as 'Plaid for commercial real estate,' Propexo lets software developers and property operators connect to 130+ property management systems - like Yardi, RealPage, AppFolio, Entrata, and Buildium - through a single, normalized API and no-code sync tool. What once took teams of engineers months to build, Propexo delivers in days, with standardized data models, webhooks, and enterprise-grade security. Founded in 2022 and a Y Combinator W2023 alum, it raised a $3.3M seed round led by Prudence in October 2023.