Is St. Mary's County, MD a Good Place to Invest in Real Estate?

Investor's Guide · St. Mary's County, MD

Short answer: for the right property at the right price, yes. St. Mary's County has something most small markets don't: a large, steady renter pool tied to NAS Patuxent River. But a strong rental market doesn't make every house a good investment, and with today's borrowing costs, the math matters more than ever. Here's how I'd evaluate an investment here, with real local numbers and an honest example.

Where the Rental Demand Comes From

NAS Patuxent River is the county's largest employer, with about 2,400 active-duty members, 9,800 civilian employees, and 5,700 contractors. Service members rotate in and out every few years, and the civilian and contractor workforce needs housing too, regardless of the PCS cycle.

You can see it in the Census numbers. In Lexington Park, right outside the gates, only 47.7% of homes are owner-occupied, compared with 73.2% for the county as a whole. Median gross rent is $1,755 a month in Lexington Park and $1,747 county-wide (Census, 2020 to 2024 estimates). Those are averages across all rentals, not what a specific home will rent for today, so I'll pull current rental comps for any property you're considering.

Where Rentals Work Best

• Lexington Park: the deepest renter pool and generally the lowest purchase prices, right at the gates.
• California: close to Gate 1 and the main shopping corridor.
• Great Mills: established neighborhoods near Gate 2.
• Leonardtown: steady demand from people who want a walkable town, at higher purchase prices.

What Makes a Good Rental Property Here?

• Commute to the gates: renters working on base pay for a short drive. Know which gate a home is near and its hours.
• Layout and size that rent easily: three bedrooms, a yard or patio, and parking tend to rent well.
• Low-maintenance systems: a newer roof, HVAC, and water heater keep your repair calls down when you're not local.
• Public water and sewer, or well-documented private systems: a septic failure is one of the most expensive surprises an investor can face here.
• HOA rules that allow rentals. Read them before you buy.
• Outside flood and high-noise zones, or priced to reflect them. Check the 2026 AICUZ maps.

How to Calculate Rental Cash Flow

Three numbers tell you most of what you need to know:

• Net operating income (NOI): rent minus operating expenses (taxes, insurance, vacancy, maintenance, management, reserves), before your mortgage.
• Cap rate: annual NOI divided by the purchase price. It compares properties regardless of how they're financed.
• Cash-on-cash return: annual cash flow after your mortgage, divided by the cash you put in (down payment, closing costs, initial repairs). It's your real return on your money.

A Worked Example (Hypothetical)

Here's a made-up but realistic-shaped example to show the math. Your numbers will differ, so plug in real quotes, real rent comps, and your lender's actual rate.

In this example, the property loses money every month even though the rent looks strong. That's the honest reality for a lot of financed rentals at today's borrowing costs. Deals tend to work when the purchase price is lower, the rent is higher, the down payment is larger, or the owner already has a low-rate loan, which is exactly why the PCS-and-hold strategy below is so common here.

Expenses Every Investor Should Budget

• Property taxes: $0.8478 per $100 of assessed value in the county, plus the state rate. A rental isn't your principal residence, so the Homestead Credit won't apply.
• Landlord insurance, plus flood insurance if the home is in a flood zone.
• Vacancy and turnover: cleaning, paint, and lost rent between tenants.
• Maintenance and capital reserves for the big-ticket items.
• Property management if you're not local.
• Lead law costs for homes built before 1978 (next section).
• HOA dues and any rental fees the community charges.
• Well and septic upkeep on homes without public utilities.

Maryland Rules Landlords Should Know

• Lead law: rentals built before 1978 must be registered with the Maryland Department of the Environment and renewed every year, and inspected for lead-contaminated dust by a certified inspector at each change in occupancy. Homes certified lead-free are exempt.
• Property managers must be licensed: in Maryland, leasing a property or collecting rent for someone else for pay is real estate brokerage work and requires a real estate license.
• Leases and security deposits follow Maryland landlord-tenant law. Use a current Maryland lease and talk with an attorney or licensed manager about the details.

More detail is in renting out your St. Mary's home when you PCS.

Financing an Investment Property

Loans for investment properties generally require a larger down payment and carry a higher rate than loans for a home you'll live in. Confirm current terms with a lender before you run numbers. Owner-occupant loans like VA and FHA require you to live in the home first, so they aren't a way to buy a pure rental. An owner who later moves out and rents the home keeps their existing loan, which is a very different position.

The PCS-and-Hold Strategy

This is the most common investment pattern in this market. A military family buys near Pax River with a VA loan, lives there for their tour, then keeps the home as a rental when they get orders elsewhere and rents it out. It often works because the owner bought with little money down and may have a lower rate than a new investment loan would carry. Before you do it, check your loan terms, your HOA rules, and the lead law if the home is older, and line up a licensed property manager. If the numbers don't work, selling may be the better move. A free home valuation lets you compare both.

Risks to Weigh

• One big employer: the local economy leans heavily on the Navy, so changes at the base would ripple through the rental market.
• Thin cash flow at today's rates, as the example shows.
• Old systems and septic that can turn into large repair bills.
• Waterfront and flood exposure that raise insurance costs. See what waterfront buyers need to know.
• Managing from afar without a good, licensed manager.

Want me to run the numbers on a specific property? Request an investment property analysis, and I'll pull real rental and sales comps for that deal.

Rent It or Sell It: A Quick Check

• Does the rent cover your mortgage, taxes, insurance, management, and reserves?
• Would you be happy owning this home for five or more years?
• Is the home in good shape, or are big repairs coming?
• Do you need the equity for your next purchase?
• Are you ready to work with a licensed property manager from afar?

If most answers point to selling, a free home valuation is the next step. If they point to renting, read how to hire a property manager before you PCS.

Sources: Military OneSource: NAS Patuxent River · U.S. Census QuickFacts: St. Mary's County · U.S. Census QuickFacts: Lexington Park · Maryland DLS 2026 county tax rates · Gordon Feinblatt on Maryland lead paint rental rules · MLS Campus on Maryland property manager licensing. Checked October 2026; rules and rates change, so confirm anything that affects your decision.