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3720 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,914 sqftBuilt 2005

Property at a Glance

This home is estimated between $293,272 and $480,356, with a best estimate of $364,170. 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

$293,272 $480,356
Best Estimate
$364,170
WCAD Value
$331,294
Medium Confidence

Based on 5 comparable properties(4 in the same subdivision)

Based on 5 comparable properties (4 in the same subdivision, 1 nearby), the estimated range is $293,272 and $480,356. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

3730 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
4 bed 2 bath 1,554 sqft Built 2008
Raw Value $378,514
Adjusted Value $474,205

Adjusted +$83,357 for 360 sqft more living space and +$12,334 for being newer. Net adjustment: +$95,691.

1584 HAYNIE BND, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,700 sqft Built 2006
Raw Value $310,508
Adjusted Value $364,170

Adjusted +$49,551 for 214 sqft more living space and +$4,111 for being newer. Net adjustment: +$53,662.

3 bed 2 bath 1,936 sqft Built 1998
Raw Value $344,623
Adjusted Value $310,750

Adjusted -$5,094 for 22 sqft less living space and -$28,779 for being older. Net adjustment: -$33,873.

1588 HAYNIE BND, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
4 bed 2 bath 1,388 sqft Built 2006
Raw Value $354,452
Adjusted Value $480,356

Adjusted +$121,793 for 526 sqft more living space and +$4,111 for being newer. Net adjustment: +$125,904.

3740 SANDY BROOK DR, ROUND ROCK, TX 78665
0.04 mi 100% similar Same subdivision
3 bed 2 bath 2,118 sqft Built 2007
Raw Value $332,284
Adjusted Value $293,272

Adjusted -$47,235 for 204 sqft less living space and +$8,223 for being newer. Net adjustment: -$39,012.

The Neighborhood

This home is in line with the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. 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
$331,294
Median
$328,056

This home is +1.0% above the subdivision median.

Tax Analysis

The estimated annual property tax is $5,961 across all districts. With a homestead exemption claimed, that drops to $4,649 — saving $1,312 per year. That's $387 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%$2,959
Round RockCity0.3720%$1,232
Williamson CountyCounty0.3694%$1,224
Austin Community Collegespecial0.1034%$343
Williamson County FM/RdCounty0.0443%$147
Upper Brushy Creek WCIDWater0.0170%$56
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,961

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $364,170 would pay approximately $2,273 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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