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3515 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,239 sqftBuilt 2002

Property at a Glance

This home is estimated between $120,934 and $392,474, with a best estimate of $170,141. 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

$120,934 $392,474
Best Estimate
$170,141
WCAD Value
$367,684
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 $120,934 and $392,474. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3513 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 963 sqft Built 2002
Raw Value $311,097
Adjusted Value $392,474

Adjusted +$81,377 for 276 sqft more living space. Net adjustment: +$81,377.

3517 SANDY BROOK DR, ROUND ROCK, TX 78665
0.01 mi 100% similar Same subdivision
3 bed 2 bath 1,592 sqft Built 2003
Raw Value $277,988
Adjusted Value $170,141

Adjusted -$104,080 for 353 sqft less living space and -$3,767 for being older. Net adjustment: -$107,847.

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 $168,722

Adjusted -$112,925 for 383 sqft less living space. Net adjustment: -$112,925.

3519 SANDY BROOK DR, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,823 sqft Built 2004
Raw Value $300,657
Adjusted Value $120,934

Adjusted -$172,188 for 584 sqft less living space and -$7,535 for being older. Net adjustment: -$179,723.

1720 AMISTAD WAY, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,263 sqft Built 2002
Raw Value $363,684
Adjusted Value $356,608

Adjusted -$7,076 for 24 sqft less living space. Net adjustment: -$7,076.

The Neighborhood

This home is valued 18.1% 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
$367,684
Median
$311,433

This home is +18.1% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,616 across all districts. With a homestead exemption claimed, that drops to $5,297 — saving $1,319 per year. That's $441 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%$3,284
Round RockCity0.3720%$1,368
Williamson CountyCounty0.3694%$1,358
Austin Community Collegespecial0.1034%$380
Williamson County FM/RdCounty0.0443%$163
Upper Brushy Creek WCIDWater0.0170%$63
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,616

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $170,141 would pay approximately $1,062 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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