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12003 GREY ROCK LN, AUSTIN, TX 78750

AUSTIN, 78750 — williamson County

3 bed2 bath1,444 sqftBuilt 1977

Property at a Glance

This home is estimated between $292,922 and $354,969, with a best estimate of $341,618. That places the property below the R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD median of $387,608, in a neighborhood that declined 7.3% over the past year.

Estimated Value Range

$292,922 $354,969
Best Estimate
$341,618
WCAD Value
$387,232
High Confidence

Based on 5 comparable properties(5 in the same subdivision)

Based on 5 comparable properties in R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD, this home's estimated market value is between $292,922 and $354,969. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

12005 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,476 sqft Built 1977
Raw Value $349,500
Adjusted Value $341,618

Adjusted -$7,882 for 32 sqft less living space. Net adjustment: -$7,882.

12001 GREY ROCK LN, AUSTIN, TX 78750
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,381 sqft Built 1977
Raw Value $339,451
Adjusted Value $354,969

Adjusted +$15,518 for 63 sqft more living space. Net adjustment: +$15,518.

12005 ACORN CREEK TRL, AUSTIN, TX 78750
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,533 sqft Built 1977
Raw Value $359,955
Adjusted Value $338,032

Adjusted -$21,923 for 89 sqft less living space. Net adjustment: -$21,923.

12007 GREY ROCK LN, AUSTIN, TX 78750
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,381 sqft Built 1977
Raw Value $339,451
Adjusted Value $354,969

Adjusted +$15,518 for 63 sqft more living space. Net adjustment: +$15,518.

12009 ACORN CREEK TRL, AUSTIN, TX 78750
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,617 sqft Built 1984
Raw Value $370,472
Adjusted Value $292,922

Adjusted -$42,614 for 173 sqft less living space and -$34,936 for being older. Net adjustment: -$77,550.

The Neighborhood

This home is in line with the R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD median of $387,608. Note that values in this subdivision declined 7.3% over the past year.

R3P5480G - Anderson Mill 12,16 - 20 - Partially in TCAD

typical
834 Properties
$387,608 Median Value
-7.3% YoY Change
2% Have Pool
97% Have Garage
This Home
$387,232
Median
$387,608

This home is -0.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $8,038 across all districts. With a homestead exemption claimed, that drops to $6,310 — saving $1,728 per year. That's $526 per month a buyer should budget. The assessed value increased -0.2% vs the subdivision average of -7.3%. This above-average increase gives a protest opportunity score of 36 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$3,458
AustinCity0.5240%$2,029
Williamson CountyCounty0.3694%$1,431
Anderson Mill Limited Districtspecial0.1243%$481
Austin Community Collegespecial0.1034%$400
Williamson County FM/RdCounty0.0443%$172
Upper Brushy Creek WCIDWater0.0170%$66
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0756%$8,038
36 / 100

Some opportunity.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $341,618 would pay approximately $2,132 per month (principal and interest only, excluding taxes and insurance).

Data sourced from Williamson County Appraisal District (WCAD), Texas Education Agency (TEA), and Federal Reserve Economic Data (FRED). Assessment values reflect the appraisal district's estimate, not market sale prices. Report generated 4/18/2026.

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