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3644 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed1,416 sqftBuilt 2006

Property at a Glance

This home is estimated between $216,585 and $441,376, with a best estimate of $434,537. 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

$216,585 $441,376
Best Estimate
$434,537
WCAD Value
$326,193
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 $216,585 and $441,376. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3648 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,050 sqft Built 2006
Raw Value $356,630
Adjusted Value $441,376

Adjusted +$84,746 for 366 sqft more living space. Net adjustment: +$84,746.

3640 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,050 sqft Built 2006
Raw Value $349,938
Adjusted Value $434,684

Adjusted +$84,746 for 366 sqft more living space. Net adjustment: +$84,746.

1563 HAYNIE BND, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,887 sqft Built 2007
Raw Value $321,532
Adjusted Value $216,585

Adjusted -$109,058 for 471 sqft less living space and +$4,111 for being newer. Net adjustment: -$104,947.

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 $434,537

Adjusted +$84,746 for 366 sqft more living space. Net adjustment: +$84,746.

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 $220,807

Adjusted -$103,733 for 448 sqft less living space. Net adjustment: -$103,733.

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
$326,193
Median
$328,056

This home is -0.6% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,869 across all districts. With a homestead exemption claimed, that drops to $4,559 — saving $1,310 per year. That's $380 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%$2,913
Round RockCity0.3720%$1,213
Williamson CountyCounty0.3694%$1,205
Austin Community Collegespecial0.1034%$337
Williamson County FM/RdCounty0.0443%$145
Upper Brushy Creek WCIDWater0.0170%$55
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,869

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $434,537 would pay approximately $2,712 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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