Mark
Murphy

A trillion dollars a month, and a spreadsheet to hold it

Every month, real estate in the United States spends something close to a trillion dollars on itself. Renovations, lease-ups, roof replacements, ground-up towers, the slow expensive work of keeping buildings standing and profitable. Mark Murphy spent the early part of his career on the finance side of that machine, and what he kept noticing was the gap between the size of the numbers and the crudeness of the tools holding them. Billion-dollar capital programs, run on email threads, PDF invoices, and a workbook with forty tabs that one person on the asset-management team understood and nobody else dared touch.

Murphy is the co-founder and CEO of Banner, a New York company that calls itself the operating system for real estate teams. The pitch is unglamorous and exactly the point: take the communications, the workflows, the spreadsheets, and the file-sharing that currently live in a dozen disconnected places, and move them into one system. From building acquisition to disposition. Banner says customers automate away more than 80% of their administrative work and save up to 10% on project costs. In an industry where a 10% saving on a capital project can be a seven-figure swing, that is not a rounding error.

The unglamorous problems are usually the durable ones. Consumer apps come and go on the tides of taste. The back office of commercial real estate has been waiting for software that actually fits its shape since the spreadsheet was invented. Murphy's bet is that the company who builds the connective tissue for capital spend gets to sit underneath every project an owner runs, forever. By 2024, Banner crossed $10 billion in capital expenditure under management. That is the number that tells you the bet is landing.

The reunion that became a company

Banner did not start in a finance conference room. It started at the University of California, Berkeley, in 2015, where Murphy met Kunal Chaudhary. They went their separate ways. Murphy into real estate finance, with stops connected to Goldman Sachs and RBC Capital Markets, plus a detour most people skip over in his bio: he co-founded Players' Lounge, a startup in the world of competitive console gaming. From bonds to button-mashing and back to buildings is not the cleanest career line you will ever see, and that is part of what makes it interesting.

Years later, Murphy and Chaudhary reconnected. Murphy had the scar tissue from inside real estate; Chaudhary, a UC Berkeley engineer, had the chops to build software for genuinely complicated workflows. They started Banner in 2019 and landed in Y Combinator's Summer 2019 batch. The division of labor was clean. One founder knew exactly where the industry hurt. The other knew how to make the pain go away in code.

What the software actually does

Here is the trick that makes real estate people lean in. Banner does not demand that anyone abandon their spreadsheet. It reads it. The platform uses optical character recognition to pull data straight out of the workbooks and invoices teams already use, then automatically reconciles that data against the accounting systems of record - Yardi, MRI Software, Entrata. Budgeting, project bidding, scheduling, contracting, invoicing: the whole messy relay of a capital project gets stitched into one continuous thread instead of forty disconnected ones.

It is a quietly radical design choice. Most enterprise software fails in real estate because it asks an industry allergic to change to change everything at once. Banner meets the spreadsheet where it lives, then slowly makes it unnecessary. The customer never has to jump. They just look up one day and notice the cliff is gone.

When Blackstone invests in the company watching Blackstone's spreadsheets

In October 2023, Banner announced a $10 million Series A, lifting total funding to roughly $13 million. The cap table reads like a list of people who would know whether the problem is real: Blackstone Innovations Investments, Fifth Wall, Pruven Capital, Basis Set Ventures, and Y Combinator. When the largest owner of commercial real estate on the planet writes a check into the software that tracks capital projects, it is a fairly strong signal that the spreadsheet problem is not imaginary.

The customer roster carries the same weight. Banner's early adopters skew toward the heavy end of multifamily and institutional operators: LivCor, Starwood Capital, Morgan Properties, April Housing, Harbor Group International, and Industrious. Murphy's stated next move is breadth - take what works in multifamily and push it into office, retail, and industrial, the other corners of an enormous market still running on the same patchwork.

The customers, in Banner's own words:

Speed as a value, not a slogan

Banner runs on four stated principles - clients first, excellence, trust, and speed - and the last one is the tell. "Speed" shows up because real estate operations do not pause for a software roadmap. Deals close on their own clock, draws come due, contractors need answers. A platform that handles a team's critical financial data has to ship at the pace of the work it is replacing, or it gets routed around. Murphy's team frames trust the same blunt way: clients hand Banner the numbers that decide whether a project makes money, so the platform earns its keep by being boringly reliable.

There is a through-line from the gaming startup to the proptech one, even if it is not obvious. Both are about taking a chaotic, high-stakes thing people care deeply about and giving it structure, a scoreboard, a single source of truth. Murphy keeps choosing problems where the stakes are real and the existing tools are improvised. Banner is that instinct pointed at the biggest asset class in the world.

The arc from here is not subtle. Across 2025, Banner widened its footprint beyond capex into project management, vendor coordination, and operating expenses - the natural sprawl of a company that wants to be the system of record rather than a single feature. The further it spreads inside an owner's operations, the harder it is to remove. That is the whole game, and Murphy is playing it deliberately.

The fast facts

For all the institutional money and the ten-figure numbers, the thing Murphy is really selling is calm. An owner with a hundred buildings and a hundred capital projects has a hundred ways to lose track of a dollar. Banner's promise is that none of those dollars goes dark. Unglamorous, yes. Also exactly the sort of thing that, once it works, nobody can imagine living without.

Why multifamily first, and why now

There is a reason Banner planted its flag in multifamily before reaching for the rest of the market. Apartment portfolios run on volume: thousands of units, endless turns, a constant drumbeat of renovations and capital projects that repeat at scale. It is the corner of commercial real estate where the spreadsheet pain compounds fastest, which makes it the corner where a single source of truth pays off soonest. Banner's early customers - the LivCors and Morgan Properties of the world - manage portfolios measured in the tens and hundreds of thousands of units. Solve the chaos there and you have proof that travels.

The timing is not an accident either. Capital has gotten more expensive, owners have gotten more disciplined, and the tolerance for losing 10% of a project budget to disorganization has shrunk accordingly. When money was cheap, sloppiness was survivable. When it is not, the value of knowing precisely where every dollar of a capital program sits goes from nice-to-have to non-negotiable. Murphy's company arrived with the answer right as the question got urgent. That is the kind of alignment between product and moment that founders spend careers waiting for.

The expansion path Murphy describes follows the money outward. From multifamily into office, retail, and industrial - the same workflow problem wearing different clothes. And from capex into the adjacent territory of project management, vendor coordination, and operating expenses. Each step deepens Banner's grip on the day-to-day of an owner's operations, and each step makes the product harder to pull out. Software that merely reports on a process can be swapped. Software that runs the process becomes infrastructure.

It helps that the founding pair maps cleanly onto the problem. Murphy carries the domain knowledge - the lived experience of watching capital programs lurch forward on improvised tools - while Chaudhary, the Berkeley engineer, brings the discipline of building software for workflows that refuse to be simple. The pairing is the oldest good idea in startups: someone who feels the pain deeply, partnered with someone who can make it stop. Banner is what happens when both halves are genuinely strong.

Ask what kind of company Banner is trying to become and the answer is hiding in plain sight in that one repeated phrase - the operating system for real estate teams. Operating systems are not features. They are the thing everything else runs on top of, the layer you forget is there precisely because it never lets you down. Murphy is not chasing a flashy product moment. He is chasing permanence. The least glamorous ambition in technology, and quietly one of the most valuable.