MRI Living Multifamily Glossary of Terms

Whether you’re onboarding a new team member in the leasing office or just looking to brush up on the most essential housing terms, we’ve got you covered. Consider this multifamily glossary your go-to guide for the most important terms you need to know in multifamily, affordable, and public housing.

Financial Management and Formulas

Accrual Accounting: Records all income and expenses in the period they were earned or incurred, regardless of when things were received and/or paid.

Breakeven Occupancy Ratio: Calculates the occupancy needed to pay all operating expenses, debt service, and any replacement reserves. The ratio is calculated using (OE + DS + RR) / EGI.

Bad Debt: Rental income you are unable to collect as a result of non-payment

Capital Expenses (CE): Expenses associated with significant improvements, such as appliances, HVAC equipment, roofing, and other major property enhancements.

Cash Flow: The amount remaining after all sources of income are collected and all property operating expenses, including capital expenditure and/or replacement reserves and debt services are paid.

Fixed Expenses: Constant amounts unaffected by occupancy fluctuations, encompassing property taxes and insurance premiums.

Net Operating Income (NOI): The total revenue that remains after all operating expenses, but before mortgage debt services and capital expenses (or replacement reserves) are subtracted.

Offline Units: This refers to apartment units unable to drive revenue. For example, model units, employee units, units undergoing maintenance or renovations, etc.

Operating Budget: Once a property is fully leased and operating under stable conditions, budgeting becomes more routine.

    • Reflects fluctuating expenses from month to month.
    • Utility expenses will vary based on seasonality (i.e. heating and cooling, snow removal, etc.)
    • Detailed goals are typically established by your supervisor, aligning with the owner’s investment goals and objectives. Deadlines for these goals are often dictated by a property’s management agreement.

Operating Expense: The total expenses (fixed and variable) of operating a property. Does not include capital items provided in the operating statement.

Replacement Reserve (RR): Integrated within Capital Expenses (CE), the Replacement Reserve serves as a designated fund for earmarking money to cover anticipated future expenses or large projects. Regular deposits ensure the availability of funds for upcoming initiatives. Some lenders may mandate a Replacement Reserve and commonly oversee disbursements from the fund.

Return on Investment (ROI): Gauges the rate of return based on income and helps determine the efficiency of an investment. To calculate, use the following formula (Gain – Cost) / Cost = ROI.

Vacancy: The loss of possible income due as a result of vacant units.

Variable Expenses: Adjustable costs subject to change based on conditions including utilities, maintenance, landscaping, marketing, payroll, etc. Many of these expenses are linked to occupancy and are frequently calculated per square foot, per unit, and/or as a percentage of total expenses.

Types of Housing

Affordable Housing: Decent and safe housing made accessible for individuals who generally earn less than 60% of the area median income (AMI). This housing typically benefits from federal, state, or private subsidies.

Affordable Housing: Project Based Section 8: A form of affordable housing that offers rental subsidies to eligible residents living in newly constructed, rehabilitated, and existing rental and cooperative apartment projects.

Some rents are subsidized by HUD under Section 8 New Construction, Substantial Rehabilitation, and/or Loan Management Set-Aside (LMSA) programs.

Assistance is “project-based,” meaning a subsidy is committed by HUD for the assisted units of a specific mortgaged property for a contractually determined period.

Military Housing: The government’s military services can engage in agreements with private developers to own, maintain, and manage military housing.

The Military Housing Privatization Initiative (MHPI) was established to attract private sector financing, expertise, and innovation to meet the housing needs of the military.

The Department of Defense collaborates with the private sector to revitalize military housing, utilizing financial programs like direct loans, loan guarantees, equity investments, or the conveyance or leasing of land.

Military members receive a Basic Allowance for Housing (BAH) to cover housing costs, giving them the choice to live in military housing or the private sector.

Senior Housing: Housing specifically designed and operated for individuals who are 55 and older. It can be either conventional market-rate housing or affordable housing. Some senior housing may offer services to help seniors remain in their homes longer.

Note: There are varying types of senior housing, including independent living, assisted living, and Full Service / Continuing Care Retirement Communities.

Student Housing: Apartment communities specifically designed for college students. These can take the form of garden-style, low-rise, mid-rise, or high-rise structures. Typically configured around a shared living room and kitchen with private bedrooms, these units may feature private or shared bathrooms. Leasing is often done by the bed. High-end student properties may offer additional amenities such as fitness centers, pools, game rooms, and more.

Types of Buildings

Duplex: Building with two separate apartment units, typically side by side but occasionally arranged on different floors. Each unit maintains its own entrance.

Garden Style: A building style where the structures are usually no more than three stories tall, featuring multiple apartments per story. These buildings are often surrounded by landscaped grounds and are usually arranged with interior courtyards that are open at one end. Parking is typically located in front of the buildings or along the perimeter. Each unit in a garden-style community has its own building entrance, often through an open breezeway, or shares an entrance via a stairwell and interior hallway that connects to other units immediately above and/or below it. Individual units only occupy one level, and buildings in this style often do not have elevators.

High-rise: High-rise buildings have more than 10 floors with an elevator service to access every floor. Residents usually enter through a common lobby, and units are located on each floor accessible from a common hallway. Many high-rise buildings have attached parking structures, which can be either below ground or adjoining the main building.

Low-rise: Low-rise buildings are typically enclosed structures that have no more than four stories. Some organizations define them as structures that are no taller than 115 feet. In low-rise buildings, units are typically accessed from a common hallway and may or may not be equipped with elevators.

Mid-rise: Mid-rise buildings are enclosed structures that typically have five to 10 stories with an elevator service. Some mid-rise buildings have attached parking structures, which can be either below ground or adjoining the main building, providing convenient parking options for residents.

Mixed Used: Refers to single buildings or a group of buildings that have multiple uses, which can include residential, commercial, industrial, cultural, or institutional purposes. In mixed-use developments, “walkability” is highly embraced and promoted.

Triplex: Buildings that consist of three apartment units, divisions, or floors. In a triplex, each unit typically has its own entrance, although there may be a main entrance for the entire building. This configuration provides separate living spaces for the occupants of each unit.

Townhouse: Townhouses are generally multi-story structures where units are attached to each other side by side. Units in townhouses may share common walls, depending on whether they are in a center or end position within the building. Townhouse buildings can be grouped together in smaller units, such as duplexes or triplexes, or they can be part of a larger community.

Legal Responsibilities

American with Disabilities Act (ADA): This act mandates that all of a multifamily community’s public areas must be readily accessible to and usable by individuals with disabilities.

Fair Housing Act (FHA): Under the FHA, individuals with disabilities are entitled to request reasonable modifications and/or accommodations to ensure equal use and enjoyment of all features, amenities, and benefits of a rental community and its policies. This provision is designed to promote inclusivity and eliminate discrimination against individuals with disabilities in housing. Landlords and property managers are required to engage in an interactive process with residents to reasonably accommodate their needs, fostering an environment that is accessible and welcoming to everyone.

Habitability: Habitability refers to the suitable maintenance of housing properties, ensuring they meet certain legal standards for the well-being and safety of residents.

Responsibilities for Habitability Maintenance:

  • Repair and Maintenance: Landlords are responsible for addressing and repairing safety hazards.
  • Compliance with Codes: Properties must be maintained according to all applicable building codes enforced through local, state, and federal statutes.

Legal Requirements for Habitability:

  • Protection from Weather: Adequate protection from weather conditions, including a sound roof, walls, and windows.
  • Essential Utilities: Provision of working water, heat, air conditioning, electricity, plumbing, and lighting.
  • Waste Disposal: Must provide adequate waste disposal facilities.
  • Clean Common Areas: Maintenance of clean and safe common areas, lobbies, and stairwells.
  • Elimination of Hazards: Efforts to eliminate or warn residents of environmental hazards.
  • Safety and Security: Reasonable protection from hazards and crimes.
  • Nuisance Control: Control of nuisances such as noise or overcrowding.

In the Lack of Habitability, Residents Can:

  • Report issues to local authorities, file for court action, make or hire someone themselves to make repairs, move out, withhold rent, or file suit for the difference in rent based on a more accurate value of the unit.

These legal requirements and resident options aim to ensure that housing remains safe and habitable for tenants, and they provide recourse in cases where these standards are not met.


Amenities: The features and services provided within an apartment complex or building that enhance the living experience for residents. These can include various facilities, conveniences, and recreational offerings, such as fitness centers, swimming pools, on-site parking, pet-friendly policies, in-unit appliances, security systems, communal spaces, and more.

Call to Action (CTA): A concise and compelling statement or prompt designed to encourage immediate response or engagement from the audience, often leading them to take a specific action, such as making a purchase, filling out a form, or signing up for a service. CTAs are commonly used in marketing and communication strategies to guide and convert prospective renters into residents.

Cost Per Lead (CPL): A marketing metric that measures the average cost for acquiring a potential resident or lead. It is calculated by dividing the total campaign cost by the number of leads received, providing insights into the efficiency and effectiveness of lead generation efforts.

Gross Potential Rent (GPR): Represents the total amount of rent that would be collected if a property achieved 100% occupancy, with all residents paying market rent. It serves as a benchmark for assessing the property’s revenue potential. Other income and expenses are often measured and evaluated as a percentage of GPR.

GPR = total number of units x the average market rent

Internet Listing Service (ILS): An online website that aggregates and lists apartment rental listings, providing a centralized platform for property marketing and search.

Market Segmentation: Dividing a larger market into smaller, more defined sub-markets.

Market Analysis: A structured approach to leveraging data to inform rational decision-making within the market.

Promotional Mix: The promotional mix is made up of the five components that must be addressed and at peak operating levels to achieve success in marketing efforts. Those five P’s are: People, Product, Price, Promotion, and Place.

Target Market: The individuals whom a community aims to target in its marketing and advertising efforts. This includes economic, geographic, and amenity characteristics, ensuring non-discriminatory practices.

Turnover Ratio: Calculated by dividing the total number of move-outs for a given period by the total number of apartment units. This metric serves to assess occupancy levels and potential operating expenses and is typically measured as an annual percentage.

Vacancy, concession, and collection loss (VAC): The total value of rent loss from vacant units, concessions, collection losses, and non-revenue units. Generally, 2% of GPR is an acceptable threshold for a community.


Make Ready: The act of repairing or replacing items to make a unit market-ready and meet the expectations of a future resident. This might include trash removal, pest control, appliance maintenance, painting, final cleaning, etc.


Effective Rent: The potential rent achieved if all leases are signed at scheduled market rates, accounting for any concessions granted through lease addendums.

Fair Market Rent: The amount that renting would cost without any government pricing intervention.

Rent Control: A government policy that sets a specific amount that can be charged for rent. New York City is the most prominent example in the United States.

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