According to HousingWire, Mainstay, a residential real estate data and workflow company that spun out of Opendoor last year, has secured over $18 million in new growth capital. The company also acquired Truelist, an AI-powered listing platform designed for brokers and agents. This move strengthens Mainstay's ability to offer a more complete solution by adding listing data capabilities and workflow management tools to its existing property data infrastructure.
Mainstay has built its business around solving a fundamental problem in residential real estate: the industry still operates through dozens of disconnected systems, databases, and manual processes. The company combines customer data with its own information and external sources to create a unified record for each property, and it manages everything from transaction execution to property taxes, homeowner association issues, and payment processing.
Since becoming independent from Opendoor in August 2024, Mainstay has already demonstrated significant scale. The platform has facilitated more than $12 billion in real estate transactions and serves as the infrastructure for 95 percent of the 60 largest residential real estate investors in the country. The company has also executed more than 2 million automated workflows across more than 50,000 external portals.
The financing round included both new investors like Parker89, Stackpoint, Alpaca VC, and FJ Labs, as well as existing backers such as Khosla Ventures and Era Ventures. Carey Armstrong, the founder and former CEO of Truelist, is joining Mainstay as chief strategy officer. Armstrong brings considerable experience, having previously worked as vice president of Premier Agent at Zillow and co-founded another company called Tomo.
Mainstay's leadership team sees this acquisition and capital raise as an opportunity to expand beyond the largest institutional investors and begin serving brokerages, smaller investors, and individual agents. The company plans to use its new funding to build out these additional customer segments while leveraging its proprietary data and AI-first approach.
What I am seeing locally across the Bay Area and East Bay is that brokers and agents are hungry for better tools that simplify their workflows and give them access to cleaner, more reliable data. A platform like this that can consolidate everything from listing management to transaction execution could really be a game changer for independent and smaller brokerage firms that have traditionally been squeezed between the big tech platforms and large institutional players.
