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3818 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,847 sqftBuilt 2007

Property at a Glance

This home is estimated between $246,300 and $505,535, with a best estimate of $317,762. 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

$246,300 $505,535
Best Estimate
$317,762
WCAD Value
$325,180
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 $246,300 and $505,535. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

3822 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,966 sqft Built 2006
Raw Value $304,077
Adjusted Value $272,412

Adjusted -$27,554 for 119 sqft less living space and -$4,111 for being older. Net adjustment: -$31,665.

3814 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,868 sqft Built 2006
Raw Value $326,735
Adjusted Value $317,762

Adjusted -$4,862 for 21 sqft less living space and -$4,111 for being older. Net adjustment: -$8,973.

1504 TONIA LOOP, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 2,133 sqft Built 2007
Raw Value $312,522
Adjusted Value $246,300

Adjusted -$66,222 for 286 sqft less living space. Net adjustment: -$66,222.

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 $505,535

Adjusted +$131,287 for 567 sqft more living space and -$4,111 for being older. Net adjustment: +$127,176.

3 bed 2 bath 1,864 sqft Built 2010
Raw Value $371,814
Adjusted Value $380,212

Adjusted -$3,936 for 17 sqft less living space and +$12,334 for being newer. Net adjustment: +$8,398.

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
$325,180
Median
$328,056

This home is -0.9% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,851 across all districts. With a homestead exemption claimed, that drops to $4,540 — saving $1,311 per year. That's $378 per month a buyer should budget. The assessed value increased +2.6% vs the subdivision average of -4.7%. This above-average increase gives a protest opportunity score of 37 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$2,904
Round RockCity0.3720%$1,210
Williamson CountyCounty0.3694%$1,201
Austin Community Collegespecial0.1034%$336
Williamson County FM/RdCounty0.0443%$144
Upper Brushy Creek WCIDWater0.0170%$55
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,851
37 / 100

Some opportunity.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $317,762 would pay approximately $1,983 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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