FSBAI — For Sale By AI · 909 19th St S, Arlington VA

01 The house · Staged, shot, and listed by AI AI-run

909 19th St S

Arlington, VA 22202 · Aurora Highlands

The triple lot is three original 25' × 120' platted parcels (Lots 5, 6, 7 Block 20, Addison Heights) — one block to Pentagon City Metro. Refinished light-stain hardwoods, covered front porch, rear deck, real front and back yards, oversized 1.5-car garage plus driveway for 7 cars. 2022 Trane dual-zone HVAC, Tesla Wall Connector, active radon mitigation, $70K in 2022–2026 invoice-backed improvements.

$1,785,000 Listed Apr 2026 · For Sale By AI

Bedrooms

3.5

Bathrooms

3,438

Finished sq ft

9,000

Lot sq ft (3 platted)

2005

Year built

EHO

2–6 unit eligible

Full listing description Read more

Rare 9,000 sq ft flat triple lot in Aurora Highlands (22202). Refreshed 5 BR / 3.5 BA, ~3,500 sq ft home (3,400+ measured) with a large covered front porch, rear deck, and spacious yard. ~$70K in invoice-backed 2022–2026 improvements. Suburban-scale yard with urban walkability.

Walkability & location

Walkable to Crystal City Metro, Pentagon City Metro, Amazon HQ2, Virginia Tech Innovation Campus, Costco, Whole Foods, Pentagon City mall, and the Pentagon itself. Long Bridge Park and the Mt. Vernon Trail within walking distance.

Outdoor living

Large covered front porch and a rear deck. Three original 25' × 120' platted lots (Lots 5, 6, 7 Block 20, Addison Heights; 9,000 sq ft total) give you a proper front yard and backyard — scale that simply doesn't exist in most of the neighborhood. East-facing front with morning light. Professionally landscaped front and back with new sod, new trees, and seasonal plantings. Oversized 1.5-car garage plus a driveway that fits 8 vehicles — unusual inside the neighborhood's permit-parking zones.

Inside

Refinished light-stain hardwood floors. Updated lighting, plumbing, and vanity fixtures throughout (2026). Gas-log fireplace. Vinyl double-pane windows. Separate exterior basement stairwell gives the lower level its own walk-out access — potential in-law or guest suite.

Kitchen & laundry

New KitchenAid 30" gas cooktop (2026), new LG 27 cu ft InstaView side-by-side refrigerator with Craft Ice (2025), and an LG 5.0 cu ft Mega Capacity front-load washer (2020). Washer and dryer included.

5th bedroom

The 5th bedroom conversion is complete and is awaiting Arlington County inspection and permit approval, which will be finalized prior to closing. Included a code-compliant basement egress window professionally installed (April 2026) and hardwired smoke detectors.

HVAC & systems

Two independently zoned systems.

Upper zone (2nd floor + attic) — 2022 Trane install, under Trane manufacturer warranty:

Trane 16 SEER 2-ton A/C (T4TTR6024)
Trane variable-speed gas furnace (TTUD2B060A9V3VB), attic-located
Trane cased coil (T4PXCBU30BS3HAA)
Trane communicating thermostat
UV air scrubber (9/1/2022)

Lower zone (first floor + basement):

Google Nest Learning thermostat + 2 Nest Temperature Sensors (installed 4/2026)
Aprilaire 800 whole-house steam humidifier, digital humidistat (2022)
UV air scrubber (9/1/2022)

Also: active radon mitigation. Tesla Wall Connector Gen 4 (48A / 11.5 kW, NACS + switchable J1772 adapter) outside the garage.

Schools

Abingdon Elementary · Gunston Middle · Wakefield High.

All improvements and refresh decisions on this home were made by the seller in consultation heavily with AI tooling.

· Comparables · How $1,785,000 was set AI-built CMA

· Comparables · Why $1,785,000 AI-built CMA

This home is genuinely hard to price. So the comparison was done three different ways — and they all agree.

There is no direct comp for 909 in Aurora Highlands today. AI built the analysis the way an appraiser would: hold what matters constant, adjust everything else, and triangulate from independent angles.

909 is priced $461K under what comparable homes are worth (all primary factors being equal)

Three things make 909 hard to comp directly:

The lot is unusual. 9,000 sq ft is roughly 50% larger than typical Aurora Highlands parcels (5,000–6,500 sf). Assembled from three platted lots — EHO-eligible for 2–6 unit redevelopment under Arlington's 2023 zoning reform. AI surveyed every parcel in the neighborhood and found only nine lots of 9,000+ sq ft.
The vintage falls in a comp gap. Aurora Highlands inventory is bimodal: renovated 1920s–50s colonials (2,400–3,500 sf) and 2024–26 new construction at $2.23M–$2.58M. 909, built 2005, sits between — modern systems, open floorplan, well below new-build pricing.
The walk-out lower level adds 1,020 sq ft at near-market $/sf — true livable space (5th BR, full bath, family room, direct yard access), not a discounted basement.

A New construction & large-lot comps · 22202

Address	Status	Price	2026 adj^*	Finished sf	Lot (sf)	Built	$/sf land
909 19th St S This home	Active	$1,785,000	$1,785,000	3,438	9,000	2005	$198
921 22nd St S Same parcel size, parallel street	Coming 5/16	$2,575,000	$2,575,000	5,563	9,000	2026	$286
637 21st St S	Sold 12/25	$2,340,000	$2,385,000	4,554	~4,500	2024	$530
1015 20th St S	Sold 8/25	$2,225,000	$2,300,000	4,634	5,663	2025	$406
2155 S Ives St Age peer · 2009 build	Sold 2/24	$1,650,000	$1,840,000	3,968	6,238	2009	$295

^*Time-adjusted to April 2026 at 5%/yr Arlington single-family appreciation (Bright MLS 12-mo median, 2024–26).

Three new-construction comps in immediate Aurora Highlands establish a band of $2.23M–$2.58M. 909 is listed at $1,785,000 — $440K below the floor, $790K below the same-parcel-size ceiling at 921 22nd St S. On $/sf-of-land, 909 is the lowest in the set ($198) despite tying for the largest lot.

B Adjustment grid · every comp normalized to 909's specs

Methodology. For each comp: (1) extract land value at $145/sf land basis to back into structure value, (2) depreciate that structure to 909's effective age (21 yrs) using standard appraisal age curves, (3) adjust building size at $150/sf marginal cost, (4) recombine with 909's 9,000 sf land at $1,305,000. Standard paired-sales appraisal practice.

Comparable	2026 price	Vintage adj¹	Size adj²	Lot adj³	909-equivalent	vs $1.785M list
921 22nd St S 5,563 sf · 9,000 lot · 2026	$2,575,000	−$273,000	−$319,000	$0	$1.983M	+$198K · +11%
637 21st St S 4,554 sf · 4,500 lot · 2024	$2,385,000	−$320,000	−$167,000	+$652,000	$2.550M	+$765K · +43%
1015 20th St S 4,634 sf · 5,663 lot · 2025	$2,300,000	−$296,000	−$179,000	+$484,000	$2.309M	+$524K · +29%
2155 S Ives St 3,968 sf · 6,238 lot · 2009 age peer	$1,840,000	−$19,000	−$80,000	+$401,000	$2.142M	+$357K · +20%
Mean / median adjusted value	—	—	—	—	$2.246M / $2.226M	+$461K / +$441K

¹ Vintage: structure value (price minus land) depreciated from comp's age to 909's age 21 on standard appraisal curve. ² Size: (comp sf − 909's 3,438 sf) × $150/sf marginal cost. ³ Lot: (909's 9,000 sf − comp lot sf) × $145/sf land basis.

Even after normalizing every comp to 909's exact specs — same age, same building size, same lot size — every adjusted value sits above the $1,785,000 list. The age peer (2155 S Ives, where vintage adjustment is minimal) implies $2.142M alone. Across all four independent comps, the implied 909-equivalent value averages $2.246M — a $461K premium to list (26%).

C Land-basis triangulation · two independent methods

Method	Date	Price	2026 adj	Lot (sf)	$/sf land	Note
921 22nd St S — raw land	Jul 2023	$1,100,000	$1,260,000	9,000	$140	Direct teardown sale, identical parcel size
637 21st St S — extracted basis	2024 teardown	~$820,000	~$900,000	~6,000	$150	Implied land basis from $2.34M new-build sale
909 — triangulated land value	Today	—	$1.26M – $1.35M	9,000	$140 – $150	Two methods converge

What this means at $1,785,000

Take the midpoint of the land range — $1.30M for the dirt. That leaves roughly $485,000 attributable to a 3,438 sq ft 2005-built structure with 5 BR / 3.5 BA and a finished walk-out lower level. That's $141/sf for the structure alone — well below current Northern Virginia replacement cost of $325–$400/sf for comparable build quality. A buyer at $1,785,000 acquires the lot at fair market and the structure at a meaningful discount to building new.

All comps from Bright MLS, Arlington County tax records, and Redfin/Zillow public listings as of April 2026. Full CMA, disclosures, and inspection report available on request.

02 Money in · What's been put into 909 19th St S Receipted

~$70K in invoice-backed upgrades.

Every line item is receipted. Roughly 55% major renovation, 21% a 2022 Trane HVAC system still under warranty, 12% the 2026 code work that turns the basement into a legal 5th bedroom.

$68,575.98 itemized · ~$70K with pending

Major renovations55%

$38,250.00

General contractor & handyman ($13,000) · floor refinishing — light-stain hardwoods ($14,000) · front + back landscaping with new sod, trees, seasonal plantings ($11,250)

HVAC & climate21%

$14,383.07

2022 Trane HVAC — 16 SEER A/C, variable-speed gas furnace, Aprilaire 800 steam humidifier, 2× UV air scrubbers, maintenance plan ($13,700) · Google Nest install ($440.33) · Nest hardware + 2 temp sensors ($242.74)

5th-bedroom code compliance12%

$8,300.00

Clifton Contracting basement package — code-compliant egress window + 2 hardwired smoke detectors, April 2026. The work that legally enables the 5th bedroom.

Kitchen appliances6%

$4,051.98

KitchenAid 30" gas downdraft cooktop ($2,249.99, Best Buy) · LG 27 cu ft InstaView side-by-side refrigerator with Craft Ice ($1,801.99, Costco 6/2025)

Backyard / kids3%

$1,740.94 + install pending

Gorilla Playsets "Outing w/ Monkey Bars" cedar swing set, Aug 2021. Professional install figure pending.

Fixtures & lighting1.5%

$1,000.00

Jensen medicine cabinets, replacement bulbs and hardware throughout.

Laundry1.2%

$849.99

LG 5.0 cu ft Mega Capacity front-load washer in black (Costco 11/2020).

Conveying at no costincluded

Tesla Wall Connector Gen 4 (switchable J1772 adapter)
Active radon mitigation system (installed)
Aprilaire 800 humidifier + 2× UV scrubbers

Full vendor log available on request — AI will email it to you.

06 Methodology · What "For Sale By AI" actually meant

Every decision, receipted.

Transparency is the whole product. Here's the actual log of how AI ran the sale — pricing, prep, vendors, marketing, copy. The detail is the credibility.

Pricing01 / 14

AI ran the comp analysis and found no true comp.

After scanning recent Aurora Highlands sales, AI concluded only 9 lots in the neighborhood share this triple-lot footprint. It proposed a price inside a narrow band; I chose to list slightly under to test demand velocity. The decision to undershoot is mine; the range isn't.

> propose_list_price(comps=n:42, constraints=triple_lot=true) → $1.78M–$1.82M
> choice(strategy="test demand velocity") → $1,785,000

Punch list02 / 14

Walked the house on my phone, asked AI "tell me what to do."

Frame by frame: refinish floors lighter, swap dated ceiling fans, add landscape spotlights, power wash the deck, fix every small thing a buyer notices in the first 30 seconds. I did the labor — AI ran the prioritization.

Staging03 / 14

Photographed individual fixtures. "Does this look old?"

AI returned a replace/keep list with source links. Replacement bulbs from Home Depot, swap-in vanity lights from Amazon, a specific brushed-nickel faucet for the primary bath. Zero aesthetic disputes because there was no one to dispute with.

Basement04 / 14

Turned the basement into a legal 5th bedroom.

AI identified that an egress window would reclassify the finished basement room as a conforming bedroom under Virginia code. It scoped the job, specified the window size, and drafted the contractor email. Two days of excavation, one inspection, +1 BR on the listing.

Vendors05 / 14

AI found, vetted, and booked the stager, photographer, sign printer.

It also drafted the outreach emails, monitored replies, and flagged when a vendor went cold. I signed every contract. AI wrote every first draft. No cold calls, no awkward back-and-forth.

Branding06 / 14

Even this sign, this logo, this website were AI-built.

Including the tagline, the color palette, the fence post type, and the print shop. Every element carries a small made by AI tag where you'd expect a credit line. It's self-referential on purpose — if AI can run the sale, it can build the artifacts that advertise the sale.

07 What I actually learned

AI nailed the judgment.
I did the labor (or hired people to do it).
The gap matters.

Most of what a traditional agent charges 3% for is decisions: price this at X. Stage like this. Swap this fixture. Reply with this tone. Push back on that clause. That's the judgment layer. AI does it now — quickly, cheaply, and in my experience, well.

What no software can do is climb a ladder, crimp a wire, drive to Home Depot at 9pm, or reposition a hose when the sprinkler timer misfires. I did those things. Hundreds of them. Over two weeks, with a newborn in the house. It was a lot of work, even with the decision burden removed.

So here's the honest take: I don't think most homeowners should do this. Not yet. The interesting finding isn't AI replaces realtors. It's that the judgment layer is now solved, and the execution layer is still entirely human. A robot in your house changes that equation. We're not there. But we're closer than I expected when I started.

Sub-finding · Contractors

The best-reviewed contractor on Yelp is almost never the best contractor.

Yelp, Angi, Handy, Thumbtack — they don't rank by quality. They rank by who pays to advertise and who has time to chase reviews. The contractors at the top of those lists charge more and aren't usually the ones doing the best work. The genuinely outstanding ones are heads-down, fully booked through word-of-mouth, and basically invisible online.

So I built a different way to find them.

I'll write this method up in the post-mortem. It's the most generalizable thing I learned.

TL;DR — The experiment is: when an AI runs the sale instead of an agent, can the market tell the difference? We're about to find out.

I'm selling my house
with AI.

909 19th St S

Walkability & location

Outdoor living

Inside

Kitchen & laundry

5th bedroom

HVAC & systems

Schools

Watch the house in motion.

The whole house, room by room.

Come see the experiment in person.

RSVP

This home is genuinely hard to price. So the comparison was done three different ways — and they all agree.

~$70K in invoice-backed upgrades.

Every decision, receipted.

AI ran the comp analysis and found no true comp.

Walked the house on my phone, asked AI "tell me what to do."

Photographed individual fixtures. "Does this look old?"

Turned the basement into a legal 5th bedroom.

AI found, vetted, and booked the stager, photographer, sign printer.

Even this sign, this logo, this website were AI-built.

AI nailed the judgment.
I did the labor (or hired people to do it).
The gap matters.

The best-reviewed contractor on Yelp is almost never the best contractor.

Writing about this experiment?

Press & researchers

I'm selling my housewith AI.

909 19th St S

Walkability & location

Outdoor living

Inside

Kitchen & laundry

5th bedroom

HVAC & systems

Schools

Watch the house in motion.

The whole house, room by room.

Come see the experiment in person.

RSVP

This home is genuinely hard to price. So the comparison was done three different ways — and they all agree.

~$70K in invoice-backed upgrades.

Every decision, receipted.

AI ran the comp analysis and found no true comp.

Walked the house on my phone, asked AI "tell me what to do."

Photographed individual fixtures. "Does this look old?"

Turned the basement into a legal 5th bedroom.

AI found, vetted, and booked the stager, photographer, sign printer.

Even this sign, this logo, this website were AI-built.

AI nailed the judgment.I did the labor (or hired people to do it).The gap matters.

The best-reviewed contractor on Yelp is almost never the best contractor.

Writing about this experiment?

Press & researchers

I'm selling my house
with AI.

AI nailed the judgment.
I did the labor (or hired people to do it).
The gap matters.