Controller

About Mainstay

Mainstay is the leading market intelligence platform purpose-built for buying, managing, and selling homes in the single-family rental industry. As an AI-native company, we turn complex data into clarity that helps the industry move forward with confidence. Founded within Opendoor, Mainstay launched as an independent company in 2024 and recently raised a Series A round led by Khosla Ventures.

Responsibilities

• Own the monthly, quarterly, and year-end close process in full, including journal entries, account reconciliations, and consolidations
• Prepare and take final ownership of accurate, timely GAAP financial statements and supporting management reporting packages
• Design, implement, and enforce the internal control environment as Mainstay scales, building the foundation for future audit and compliance requirements
• Set technical accounting policy — researching and documenting positions on revenue recognition, equity, leases, and other complex areas, and serving as the company's point of authority on GAAP matters
• Define and implement scalable finance and accounting data structures across the ERP, internally managed databases, and fragmented product group data assets
• Own the external audit relationship, including PBC schedules, auditor coordination, and final resolution of technical issues
• Partner with the Head of Finance on budgeting, forecasting, and variance analysis
• Partner with Legal and People teams to maintain and manage the cap table
• Build, manage, and mentor the accounting team as it grows, including hiring and development of accounting staff
• Own accounting systems and ERP strategy, driving automation and process improvement as transaction volume increases
• Lead ad hoc projects tied to fundraising, board reporting, and other strategic initiatives

Requirements

• Bachelor's degree in Accounting or Finance; CPA strongly preferred
• 10+ years of progressive accounting experience, including prior experience as a Controller or Assistant Controller
• Strong working knowledge of U.S. GAAP, with demonstrated experience owning a complete close and preparing consolidated financial statements independently
• Advanced Excel skills and experience with a modern ERP/accounting system
• Prior experience managing and developing an accounting team

Nice to Have

• Experience at a high-growth, VC-backed startup, especially one that has scaled its finance function from the ground up
• Experience working with tools such as Ramp, Rippling, Shareworks, and Sage Intacct
• Experience implementing or migrating accounting systems
• Experience managing external audit and tax return processes end-to-end
• Experience presenting financials to a board or investors