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3810 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 $197,160 and $379,268, with a best estimate of $297,672. That places the property below the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056, in a neighborhood that declined 4.7% over the past year.

Estimated Value Range

$197,160 $379,268
Best Estimate
$297,672
WCAD Value
$351,190
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 $197,160 and $379,268. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3933 BONNIE LN, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,076 sqft Built 2003
Raw Value $316,026
Adjusted Value $297,672

Adjusted -$6,020 for 26 sqft less living space and -$12,334 for being older. Net adjustment: -$18,354.

3931 BONNIE LN, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 789 sqft Built 2004
Raw Value $327,057
Adjusted Value $379,268

Adjusted +$60,434 for 261 sqft more living space and -$8,223 for being older. Net adjustment: +$52,211.

1508 TONIA LOOP, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
4 bed 2 bath 1,280 sqft Built 2006
Raw Value $378,359
Adjusted Value $325,103

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

3925 BONNIE LN, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,577 sqft Built 2003
Raw Value $331,519
Adjusted Value $197,160

Adjusted -$122,025 for 527 sqft less living space and -$12,334 for being older. Net adjustment: -$134,359.

3923 BONNIE LN, ROUND ROCK, TX 78665
0.04 mi 100% similar Same subdivision
3 bed 2 bath 1,280 sqft Built 2003
Raw Value $274,567
Adjusted Value $208,977

Adjusted -$53,256 for 230 sqft less living space and -$12,334 for being older. Net adjustment: -$65,590.

The Neighborhood

This home is valued 7.1% 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
$351,190
Median
$328,056

This home is +7.1% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,319 across all districts. With a homestead exemption claimed, that drops to $5,004 — saving $1,315 per year. That's $417 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%$3,136
Round RockCity0.3720%$1,306
Williamson CountyCounty0.3694%$1,297
Austin Community Collegespecial0.1034%$363
Williamson County FM/RdCounty0.0443%$156
Upper Brushy Creek WCIDWater0.0170%$60
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,319

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $297,672 would pay approximately $1,858 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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