54 Marwood Pl · Stony Brook, NY 11790

$688,000

4 bd · 3.0 ba · 1,812 sqft · Other · 15 Days on market

Built 1972 0.34 ac lot $380/sqft · 17% below area Est $829k · 17% under

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Why this score? — see what drove the D grade

The composite is a weighted blend of 9 inputs, each scored 0–100. Each bar is that input's sub-score; the figure is the points it added to the 100-point composite (weight × sub-score).

• ARV discount +15.0/15.0
• Schools +7.6/10.0
• Cash flow +6.3/30.0
• Livability +4.2/5.0
• Rent growth +2.5/5.0
• Condition / age +2.5/5.0
• 1% rule +2.0/10.0
• DSCR +0.6/10.0
• Appreciation +0.0/10.0

Listing remarks

Welcome to the highly sought-after “M” Section of Stony Brook, where this beautifully situated three-bedroom, two-full-bath home is tucked away on a quiet cul-de-sac on a spacious . 34-acre property. Offering both comfort and versatility, the home features a Legal one-bedroom, one-bathroom accessory apartment with valid Brookhaven permit Enjoy the convenience of nearby shopping, including Smith Haven Mall, as well as easy access to the Long Island Rail Road for commuting to New York City and throughout Long Island. The property is also close to Stony Brook University Hospital and Stony Brook University, adding to its prime location. Additional highlights include connection to se

Key facts

• Connection to sewers
• Quiet cul-de-sac
• Spacious property

Tags

• LEGAL ACCESSORY APARTMENT
• QUIET CUL-DE-SAC
• SPACIOUS PROPERTY
• NEARBY SHOPPING
• CONNECTION TO SEWERS
• PEACEFUL NEIGHBORHOOD SETTING

Property features AI

Exterior

• Parking: Driveway with space for 3 vehicles; No carport
• Utilities: Public sewer; Electricity connected; Water connected; Public trash collection
• Home design: Single family residence
• Construction: Shake siding and stone exterior
• Exterior features: Back yard; Located on a cul-de-sac; Not waterfront

Interior

• Kitchen: Dishwasher; Electric oven; Electric range; Refrigerator
• Bedrooms: Includes a first-floor bedroom
• Flooring: Carpet; Ceramic tile
• Bathrooms: Three full bathrooms
• Heating & cooling: Baseboard heating; Oil heating; Central air conditioning; Wood-burning fireplace (1)
• Interior features: First-floor bedroom; First-floor full bathroom; Eat-in kitchen; Pull-down attic stairs; No basement
• Laundry & utility: Laundry room; Washer; Dryer

What this means for you Summary

Snapshot

• This is a 4-bed/3.0-bath other listed at $688k.

Deal economics

• At list price, monthly cash flow is $-1k ($-15k/yr) — negative.
• To cash-flow at today's rent, offer at most $471k (31.6% below list).
• To meet the 1% rule (rent ≥ 1% of price), the offer needs to be $480k (30.3% below list).
• Recommended offer: $471k (31.6% below list) — sets the bar for cash-flow.
• Cap rate 4.1% vs local median 3.3% in Stony Brook — meaningfully above typical; check what's discounted (condition, days-on-market, listing class) to confirm the premium yield is real.

Location & tenants

• Location reads 85/100 on livability (#29 in NY, #515 nationally) — a professional / high-income tenant draw. Strengths: crime A+, commute A+, employment A+; Watch: cost of living F.
• Three Village Central School District (suburban): math 81% / reading 83% proficiency, ranked #31 of 590 in NY (top 5%) — strong family-tenant draw, lease renewals of 3-5y typical; only 5% free/reduced lunch — higher-income household profile.
• Zoned schools: William Sidney Mount Elementary School (math 67% / reading 67%, grade B+, #525 of 2,108 statewide, top 27%, 511 students, 17% FRL); Robert Cushman Murphy Junior High School (math 67% / reading 77%, grade A, #76 of 729 statewide, top 11%, 667 students, 18% FRL); Ward Melville Senior High School (math 97% / reading 92%, grade A+, #117 of 1,100 statewide, top 11%, 1,507 students, 15% FRL).
• Market conditions: 86 active listings in the ZIP; high-income renter base; 1,366 units permitted in Suffolk County in 2024 (216 in 5+ unit buildings).
• This rent runs 34% of the median local income ($171k/yr) — at the standard rent-burdened threshold; future hikes will face affordability resistance.

Forward outlook

• Local home prices are declining (-3.0%/yr); year-one equity from $5k of loan paydown is wiped out by about $21k of value loss. Plan a longer hold.
• Suffolk County population projected to shrink 5% by 2050 — rents likely to lag national; underwrite the cash flow, not the appreciation.

Negotiation context

• It's been on market 15 days — a 2% lower offer ($678k) is reasonable based on typical stale-listing flexibility.

Risks & watch-outs

• Climate carrying-cost: severe wind risk, 80% chance of damaging wind over 30y; extreme-heat days projected 7→16/yr by 2055 (HVAC capex compounding) — expect insurance premiums to compound above CPI over the hold.

Recommended offer $470,909 (31.6% below list)

Questions for the listing agent

1. What do current leases actually rent for vs. the listed asking? Can we see a recent rent roll and the last 12 months of T-12 income?
2. Built in 1972 — when were the roof, HVAC, electrical panel, plumbing, and water heater last replaced?
3. Is there a deadline driving the sale (1031 exchange, divorce, estate, relocation)? That informs how much negotiation room exists.
4. Schools are A-rated — typically a magnet for longer-tenancy family renters. What's the average tenant stay here, and is there a school-zone premium baked into asking?
5. The area grade is low — what's the realistic commute time and amenity access for the typical tenant pool here? Any planned neighborhood developments (good or bad) we should know about?
6. What's the average days-on-market for RENTAL listings here right now (not sales)? A rising rental-DOM trend means longer vacancies and softer asking-rent achievability than the comps imply.
7. What's the recent tenant-quality profile in this submarket — average credit score on applications, eviction rate, late-payment / NSF rate, and stable-employment percentage? A property-management company in the area should have these aggregated.
8. How much new for-sale + rental construction is in the pipeline within 1–3 miles? Heavy new supply typically softens prices + rents 12–24 months out; constrained supply supports both.

Investment metrics

• 1% rule: 0.70% ✗
• Cap rate: 4.15%
• Cash-on-cash: -7.66%
• DSCR: 0.66
• GRM: 12.0

CMA / ARV

• ARV (median comp): $828,881
• List price: $688,000
• Delta: -17.00%
• Verdict: UNDERPRICED
• Comps: 20 within 1.0 mi

Projected returns pro-forma

-3.0% appreciation · 3.0% rent growth · sell at horizon

5-year hold

• IRR: -29.6%
• Equity multiple: 0.02×
• Total profit: $-189,520
• Equity at exit: $102,583

10-year hold

• IRR: -30.3%
• Equity multiple: -0.37×
• Total profit: $-264,862
• Equity at exit: $59,486

Cash invested: $192,640 (down + closing). Projections, not guarantees.

Landlord ↔ Tenant lean methodology

• Overall (STATE): 15 Strongly Tenant-Friendly
• State New York: 15 Strongly Tenant-Friendly · D+10
• County: — inherits STATE
• City: — inherits STATE

NYC rent stabilization (~1M units); 2019 HSTPA strengthened tenant rights; courts deeply backlogged.

Methodology + full state rankings →

ZIP-level market 11790

• Active inventory: 86
• Price-to-rent: 12.0×

Monthly cashflow live

• Estimated rent: $4,797 medium
• Mortgage (P&I): −$3,608
• Tax from tax record: −$1,124 /mo · $13,491/yr
• Insurance: −$287
• HOA: −$0
• Vacancy / Maint / Mgmt: −$1,007
• Net cashflow: $-1,229

Break-even live

Break-even rent $6,353

Max offer price $470,909

Occupancy floor —

Sensitivity live

Price	-10% $-839	-5% $-1,034	+0% $-1,229	+5% $-1,424	+10% $-1,618
Rent	-10% $-1,608	-5% $-1,418	+0% $-1,229	+5% $-1,039	+10% $-850
Rate	-1.0pp $-882	-0.5pp $-1,054	base $-1,229	+0.5pp $-1,407	+1.0pp $-1,589

UW: 25.0% down · 7.5% · 30yr · 1.5% tax · 5.0% vac · 8.0% maint · 8.0% mgmt

Financing live

Cash to close

• Down payment: $172,000
• Closing costs: $20,640
• Reserves months: —
• Total cash needed: —

Listing history 2 events

1. 2026-05-15
   status Pending 739-char remark
2. 2026-04-30
   listed $688,000 Active 739-char remark

ⓘ Source: listings_history table (triggers on properties + properties_extension) + one-shot backfill from property_details.listing_events for pre-trigger history.

Tax reassessment forecast NY · Partial reset (capped growth)

• Current annual tax: $13,491 · $1,124/mo
• Projected year-2 tax: $13,491 · $1,124/mo
• Expected delta: $0/yr ($0/mo · 0.0%)

ⓘ Screening estimate from a state-policy table — verify with the county assessor before closing.

Climate risk First Street

• 🌊 Flood 1/10 Low FEMA zone X (unshaded) · 0% chance over 30 yrs
• 🔥 Wildfire 1/10 Low
• 🌡 Heat 5/10 Major 7 d/yr ≥93°F today · 16 d/yr by 30 yrs out
• 💨 Wind 8/10 Severe 80% chance of damaging wind over 30 yrs
• 🫁 Air quality 4/10 Moderate 4 unhealthy d/yr today · 5 by 30 yrs out

Taxation est. · year 1

• Rental income: $57,569
• − Mortgage interest: −$38,539
• − Property taxes: −$13,491
• − Insurance: −$3,440
• − Repairs & maintenance: −$4,605
• − Management: −$4,605
• − Depreciation: −$20,015
• Taxable loss: −$27,126
• Est. tax savings @ 24.0%: +$6,510
• After-tax cash flow: $-8,237/yr

For passive investors: Depreciation is non-cash, so a rental often shows a tax loss while cash-flowing — sheltering income. Rental losses are passive: they offset passive income freely, and up to $25,000/yr can offset ordinary (W-2) income if you actively participate and your MAGI is under $100k (phasing out to $0 by $150k); unused losses carry forward. On sale, claimed depreciation is recaptured at up to 25%, and gains may owe capital-gains tax (a 1031 exchange can defer both). Figures are a year-1 estimate at your 24.0% rate — not tax advice; consult a CPA.

Schools (NCES district)

• District: Three Village Central School District
• NCES district ID: 3628200
• Math proficiency: 81% ▼ -6.00%
• Reading proficiency: 83% ▲ 2.00%
• Median HH income: $121,671
• Composite: 76.17/100
• National rank: #113
• State rank: #31 of 590 in NY

Livability — Stony Brook

• Score: 85/100
• State rank: #29
• US rank: #515

Category grades

Amenities C Commute A+ Cost of living F Crime A+ Employment A+ Housing A+ Health & safety A+ User ratings A+

Schools grade is shown separately in the Schools card above.

Census & demographics

• Census place: Stony Brook, NY
• County: Suffolk County · 679,920 people
• City population: 21,074
• Metro: New York-Newark-Jersey City, NY-NJ-PA
• Population (ZIP): 21,074
• Household income: $171,133
• Rent vs Own: 9.5% rent · 90.5% own
• Severe rent burden: 40.0

Population outlook (Suffolk County) Hauer SSP2

• Today (2025): 1,505,262 people
• By 2030: 1,498,318 · -0.5%
• By 2040: 1,471,101 · -2.3%
• By 2050: 1,424,848 · -5.3%
• By 2075: 1,337,157 · -11.2%
• By 2100: 1,217,720 · -19.1%

Race, ethnicity, and origin ACS 2023

• Neighborhood character: Diverse neighborhood (Simpson 0.57)
• Race & ethnicity: White 60% Asian 25% Hispanic / Latino 9% Black 4% Two or more races 4%
• Hispanic origin (detail): Puerto Rican 2%
• Common ancestry: Romanian 5% Scotch-Irish 2% Russian 1%
• Foreign-born: 18% · China, Canada, South Korea
• Languages at home: 68% English-only · Chinese 13% Other Indo-European 6% Spanish 5%

Political lean MEDSL · Suffolk

• 2024 margin: Lean R (+10.0) · D 45.0% · R 55.0%
• 2008→2024 swing: -16.0pp toward R · 2008: 6.0pp · 2024: -10.0pp
• All cycles: 2024: R+10.0 2020: R+0.0 2016: R+8.2 2012: D+2.9 2008: D+6.0

Not yet ingested

• Civics: —

Market trends

• HPI YoY: ▼ -662.88%
• Current HPI: 284.601
• Rent YoY: —
• Metro: New York-Newark-Jersey City, NY-NJ-PA
• State GDP YoY: ▲ 2.60%
• F500 in state: 92

Industry mix (Fortune 500 HQ in NY)

Industry	F500 HQs	Revenue
▸Financial Services	10	$950B
▸Consumer Goods	9	$162B
▸Insurance	4	$225B
▸Telecommunications	2	$144B
▸Pharmaceuticals	2	$112B
▸Media / Entertainment	2	$69B

Price history

2 events — show timeline

• 2026-05-15 Pending — OneKey® MLS as Distributed by MLS Grid
• 2026-04-30 Listed $688,000 OneKey® MLS as Distributed by MLS Grid

Property tax history

+2.4%/yr

Latest (2025): $13,491 · +0.0% YoY. Source: county tax records.