We built Rentnoi because we lived the problem. Four days a quarter assembling variance reports from Yardi export spreadsheets — only to find budget shortfalls that had been accumulating for 45 days. There had to be a better way to see the numbers that matter, every morning, before decisions that drive them are already made.
Rentnoi is a Denver-based seed-stage company building daily NOI-variance intelligence for mid-size multifamily property operators. Our mission: give operators managing 300–3,000 units the same daily NOI visibility that institutional operators have had for a decade — without requiring a data team or a platform migration.
The company started with a specific moment. Sienna Kowalski was the regional operations director for a 12-community multifamily operator in Colorado, overseeing 1,800 units across Colorado and Utah. Each quarter, she spent four days manually building the NOI variance package for the investor call — pulling six separate Yardi export spreadsheets and reconciling them by hand. Twice during that period, she discovered a community running 11% below its NOI budget only while assembling the quarterly report. The variance had been accumulating for 45 days. The window to intervene — adjusting concessions, escalating delinquency collection, or delaying a non-urgent capital expense — had closed a month earlier. The data was all there inside Yardi. No one was synthesizing it daily into a causal view.
Sienna and co-founder Theo Marchetti — a senior software engineer who had spent four years at AppFolio building API infrastructure for property management workflows — built a Python script that pulled AppFolio exports nightly, decomposed the NOI gap into its four main drivers, and emailed a summary to the property managers each morning. After two months running that script at the Colorado operator, the portfolio’s average NOI variance dropped from 7% below budget to 2.1% below budget. Three other operators in the Denver metro heard about the tool and asked to use it. That was when it became clear the problem was not unique to one company.
Rentnoi is now a purpose-built SaaS product focused on daily NOI-variance intelligence for mid-size multifamily operators — portfolio roll-up, variance decomposition, lease-expiration risk forecasting, delinquency tracking, and investor report export — connecting directly to Yardi Voyager, AppFolio, and Entrata without requiring the operator to change their property-management workflow. We are at an early-revenue stage, working closely with a small group of operators in the US market to validate the product against real portfolios and real quarterly reporting cycles.
We work with operators managing 300–3,000 units across 2–20 communities. Request a demo and let’s look at your current NOI reporting workflow together.