Erin Onsager is a Denver-based fractional CFO and the founder of Simply Spreadsheets. She works with small business owners and real estate investors who want reliable numbers and a senior finance partner who will tell them plainly what those numbers mean.
Erin has more than 20 years of experience in commercial real estate finance, spanning mortgage brokerage, lending, asset management, and private equity. She has also served as CFO of a Colorado university. She holds an economics degree from the University of Chicago.
She is a hands-on residential real estate investor as well, with more than a decade in the business and a profit on every investment within five years. She coaches newer investors on how to evaluate a deal and run a rental portfolio like a business.
The work itself is practical: cash flow forecasts that hold up, spreadsheets that update in minutes instead of hours, and reporting that a non-numbers person can read and act on. The goal is always the same, better decisions with less guesswork.
Outside of work, Erin cooks, hosts dinner parties, travels, and camps with her dogs.
At a glance
- 20+ years in commercial real estate finance
- Former CFO of a Colorado university
- Economics degree, University of Chicago
- 10+ years as a residential real estate investor
- Fractional CFO, spreadsheet consulting, AI integration, and investor coaching
Ready to Work Together?
Book a free 20-minute call. Tell us what you are trying to figure out, and we will tell you honestly whether we can help.
Want to DIY? Grab a Spreadsheet Template
Many of the same tools Erin builds for clients are available as ready-made Excel templates. From budgeting and cash flow forecasting to rental property analysis, grab a template and start making smarter financial decisions today.
