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3640 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,050 sqftBuilt 2006

Property at a Glance

This home is estimated between $241,447 and $356,630, with a best estimate of $346,918. That places the property above the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056, in a neighborhood that declined 4.7% over the past year.

Estimated Value Range

$241,447 $356,630
Best Estimate
$346,918
WCAD Value
$349,938
High Confidence

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

Based on 5 comparable properties in R409599G - STONEY BROOK - ALL SECTIONS, this home's estimated market value is between $241,447 and $356,630. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3644 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 1,416 sqft Built 2006
Raw Value $326,193
Adjusted Value $241,447

Adjusted -$84,746 for 366 sqft less living space. Net adjustment: -$84,746.

3632 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
4 bed 2 bath 1,280 sqft Built 2006
Raw Value $372,665
Adjusted Value $319,409

Adjusted -$53,256 for 230 sqft less living space. Net adjustment: -$53,256.

1551 HAYNIE BND, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,260 sqft Built 2009
Raw Value $383,209
Adjusted Value $346,918

Adjusted -$48,625 for 210 sqft less living space and +$12,334 for being newer. Net adjustment: -$36,291.

3648 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,050 sqft Built 2006
Raw Value $356,630
Adjusted Value $356,630

This comparable closely matches the subject property's features.

1559 HAYNIE BND, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,050 sqft Built 2006
Raw Value $349,791
Adjusted Value $349,791

This comparable closely matches the subject property's features.

The Neighborhood

This home is valued 6.7% above the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. With 197 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 4.7% over the past year.

R409599G - STONEY BROOK - ALL SECTIONS

typical
197 Properties
$328,056 Median Value
-4.7% YoY Change
0% Have Pool
100% Have Garage
This Home
$349,938
Median
$328,056

This home is +6.7% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,296 across all districts. With a homestead exemption claimed, that drops to $4,981 — saving $1,315 per year. That's $415 per month a buyer should budget. The assessed value increased roughly in line with the neighborhood, so a tax protest is unlikely to yield significant savings.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$3,125
Round RockCity0.3720%$1,302
Williamson CountyCounty0.3694%$1,293
Austin Community Collegespecial0.1034%$362
Williamson County FM/RdCounty0.0443%$155
Upper Brushy Creek WCIDWater0.0170%$59
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,296

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $346,918 would pay approximately $2,165 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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