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3509 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath928 sqftBuilt 2002

Property at a Glance

This home is estimated between $77,026 and $268,536, with a best estimate of $101,167. That places the property below the R402401F - Lakeside Sub Sec 1 median of $311,433, in a neighborhood that declined 11.3% over the past year.

Estimated Value Range

$77,026 $268,536
Best Estimate
$101,167
WCAD Value
$358,632
High Confidence

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

Based on 5 comparable properties in R402401F - Lakeside Sub Sec 1, this home's estimated market value is between $77,026 and $268,536. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3507 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
4 bed 2 bath 1,244 sqft Built 2003
Raw Value $365,473
Adjusted Value $268,536

Adjusted -$93,170 for 316 sqft less living space and -$3,767 for being older. Net adjustment: -$96,937.

3511 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,622 sqft Built 2002
Raw Value $281,647
Adjusted Value $77,026

Adjusted -$204,621 for 694 sqft less living space. Net adjustment: -$204,621.

1714 AMISTAD WAY, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,499 sqft Built 2004
Raw Value $277,057
Adjusted Value $101,167

Adjusted -$168,355 for 571 sqft less living space and -$7,535 for being older. Net adjustment: -$175,890.

1712 AMISTAD WAY, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
4 bed 2 bath 1,308 sqft Built 2004
Raw Value $387,313
Adjusted Value $267,738

Adjusted -$112,040 for 380 sqft less living space and -$7,535 for being older. Net adjustment: -$119,575.

1716 AMISTAD WAY, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,586 sqft Built 2002
Raw Value $279,170
Adjusted Value $85,163

Adjusted -$194,007 for 658 sqft less living space. Net adjustment: -$194,007.

The Neighborhood

This home is valued 15.2% above the R402401F - Lakeside Sub Sec 1 median of $311,433. With 135 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 11.3% over the past year.

R402401F - Lakeside Sub Sec 1

above average
135 Properties
$311,433 Median Value
-11.3% YoY Change
1% Have Pool
100% Have Garage
This Home
$358,632
Median
$311,433

This home is +15.2% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,453 across all districts. With a homestead exemption claimed, that drops to $5,136 — saving $1,317 per year. That's $428 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%$3,203
Round RockCity0.3720%$1,334
Williamson CountyCounty0.3694%$1,325
Austin Community Collegespecial0.1034%$371
Williamson County FM/RdCounty0.0443%$159
Upper Brushy Creek WCIDWater0.0170%$61
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,453

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $101,167 would pay approximately $631 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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