Vertical Integration in Rental Housing

At the scale of a few Bronx blocks, Sandhills Real Estate, cofounded by Richard Joseph Spinelli, both holds its homes and runs them, keeping to one neighborhood and one renter market so that repairs are always a short walk away. Vertical integration is the name for that combination when it happens across the stages of a building’s life: one company develops, builds, owns and manages, rather than hiring separate firms for each step. The Institute of Real Estate Management describes the basic fork. Owners employ managers either directly or through third party management firms, whose staff are often called fee managers, and managers on staff at development companies oversee properties the company developed and still owns, sometimes from renovation through ongoing operation.¹

The owners list, line by line

The National Multifamily Housing Council publishes the NMHC 50, a set of annual rankings that includes separate lists of apartment owners, managers, developers and builders. Each owner entry on the 2025 list records units held, splits them into market rate, build to rent, subsidized and student housing units, and notes any other NMHC list on which the company appears.² Reading the owners list against those notes shows how often owning and managing sit in the same company. The 2025 edition was also the first to count build to rent homes.³ Multi Housing News keeps a separate ranking of management firms, 65 of them running more than 4.1 million units in 2025.⁷

Greystar, of Charleston, South Carolina, ranked first among owners with 122,545 units, and its entry lists it on the 2025 manager, developer and builder rankings as well.² The National Apartment Association reported that Greystar also led the managers ranking with more than 946,000 units under management and led developers with more than 8,200 units started in 2024.³ The contrast between the two figures is the point: the company manages several times as many homes as it holds, so most of the homes it manages belong to someone else. By January 2026 it operated more than a million apartments while owning about 119,000.⁵ Of its owned units, 17,005 were counted as student housing.²

MAA, second with 102,348 units, appears on the managers list and on no other.² Morgan Properties, third, and Nuveen Real Estate, fourth, carry no other list at all, which means neither shows up among the top managers.² The fifth ranked owner, a Chicago apartment company, carries the managers list. AvalonBay Communities, sixth, matches Greystar by appearing on the manager, developer and builder rankings.² The Related Companies, seventh, appears on the managers list, as do the eighth ranked owner, a Colorado company, Cortland in ninth and Edward Rose Building Enterprise in tenth.²

Of the ten top owners, then, eight also rank among the top managers. The run continues for a stretch. The Michaels Organization, Weidner Apartment Homes, Essex Property Trust, FPA Multifamily, UDR and Camden Property Trust, ranked eleventh through sixteenth, all appear on the managers list.² The pattern then breaks. The six owners ranked seventeenth through twenty second carry no other list, and a mix of both kinds follows further down.²

A count across all fifty owners gives the overall shape. Twenty of them also appear on the 2025 managers list, and six appear on the developers list.² The six developers are Greystar, AvalonBay, Dominium, Alliance Residential, Mill Creek Residential and The NRP Group, and each of those six also appears on the builders list.² Only three companies, Greystar, AvalonBay and Dominium, appear on all four rankings of owner, manager, developer and builder, which makes them the fullest examples of vertical integration the lists can show.² Alliance, Mill Creek and NRP pair development and building with ownership but do not rank among the top managers. The other thirty owners appear on no manager ranking, so the lists alone do not show who runs their homes.

Two cautions apply. The lists rank by units, so a company that manages its own buildings but falls outside the top fifty managers would not carry the note. And the manager ranking counts third party work, so appearing on it shows that a company manages at scale, not that it manages only what it holds.

What the overlap means

The rankings describe the top of the market, but the underlying choice is the same one faced by a landlord with a single building: operate in house, or hire an operator. IREM lists the employers that answer it in different ways, from property management firms that serve individual and institutional owners for a fee, to full service real estate companies with management departments, to development companies whose staff manage what the company built and still holds.¹ A vertically integrated company is the last kind grown large, and the owner operator model is the same idea at the size of one landlord. In Harvard Joint Center data on properties of 50 or more units, owner managed buildings made up just 5 percent.⁶

Industry surveys sort companies along the same line. Forty firms holding or running more than 2.2 million units answered a 2023 customer experience technology survey from NMHC and RealFoundations. More than half of them, 58 percent, called themselves owner and operator; roughly one in five, 20 percent, were pure fee managers; and the remaining 22 percent held buildings while handing some of them to outside managers.⁴ On one measure the groups split cleanly: tools that let a prospect book a tour without staff help were most common among the owner and operator firms and least common among the pure fee managers.⁴

The survey also quoted respondents on obstacles, and one entry spoke directly to the fee manager’s position. A company described as fully third party said the number of software products it had to adopt to meet different clients’ needs was a major workload, which it was addressing with a single vetting process for new vendors.⁴ An integrated company chooses one set of tools for its own buildings; a fee manager serving many owners may have to run several. The tradeoffs between the two arrangements are weighed in the comparison of in house and outside management, and the occupation itself in property management.