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3636 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath2,006 sqftBuilt 2006

Property at a Glance

This home is estimated between $357,420 and $568,276, with a best estimate of $419,021. 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

$357,420 $568,276
Best Estimate
$419,021
WCAD Value
$295,564
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 $357,420 and $568,276. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

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 $568,276

Adjusted +$172,733 for 746 sqft more living space and +$12,334 for being newer. Net adjustment: +$185,067.

3628 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,500 sqft Built 2009
Raw Value $289,525
Adjusted Value $419,021

Adjusted +$117,162 for 506 sqft more living space and +$12,334 for being newer. Net adjustment: +$129,496.

1555 HAYNIE BND, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,864 sqft Built 2006
Raw Value $324,540
Adjusted Value $357,420

Adjusted +$32,880 for 142 sqft more living space. Net adjustment: +$32,880.

1547 HAYNIE BND, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,493 sqft Built 2009
Raw Value $282,453
Adjusted Value $413,570

Adjusted +$118,783 for 513 sqft more living space and +$12,334 for being newer. Net adjustment: +$131,117.

3644 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 1,416 sqft Built 2006
Raw Value $326,193
Adjusted Value $462,805

Adjusted +$136,612 for 590 sqft more living space. Net adjustment: +$136,612.

The Neighborhood

This home is valued 9.9% below the R409599G - STONEY BROOK - ALL SECTIONS median of $328,056. That positions it competitively for buyers comparing within the neighborhood. 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
$295,564
Median
$328,056

This home is -9.9% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,318 across all districts. With a homestead exemption claimed, that drops to $4,013 — saving $1,305 per year. That's $334 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%$2,640
Round RockCity0.3720%$1,099
Williamson CountyCounty0.3694%$1,092
Austin Community Collegespecial0.1034%$306
Williamson County FM/RdCounty0.0443%$131
Upper Brushy Creek WCIDWater0.0170%$50
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,318

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $419,021 would pay approximately $2,616 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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