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3500 SANDY BROOK DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,014 sqftBuilt 2004

Property at a Glance

This home is estimated between $100,544 and $342,546, with a best estimate of $321,189. That places the property above the R402401F - Lakeside Sub Sec 1 median of $311,433, in a neighborhood that declined 11.3% over the past year.

Estimated Value Range

$100,544 $342,546
Best Estimate
$321,189
WCAD Value
$339,447
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 $100,544 and $342,546. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3502 SANDY BROOK DR, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 928 sqft Built 2003
Raw Value $305,430
Adjusted Value $334,554

Adjusted +$25,357 for 86 sqft more living space and +$3,767 for being newer. Net adjustment: +$29,124.

1301 CASA BLANCA CV, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 1,636 sqft Built 2005
Raw Value $287,703
Adjusted Value $100,544

Adjusted -$183,392 for 622 sqft less living space and -$3,767 for being older. Net adjustment: -$187,159.

1303 CASA BLANCA CV, ROUND ROCK, TX 78665
0.02 mi 100% similar Same subdivision
3 bed 2 bath 970 sqft Built 2006
Raw Value $337,108
Adjusted Value $342,546

Adjusted +$12,973 for 44 sqft more living space and -$7,535 for being older. Net adjustment: +$5,438.

3504 SANDY BROOK DR, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,592 sqft Built 2003
Raw Value $277,988
Adjusted Value $111,336

Adjusted -$170,419 for 578 sqft less living space and +$3,767 for being newer. Net adjustment: -$166,652.

1305 CASA BLANCA CV, ROUND ROCK, TX 78665
0.03 mi 100% similar Same subdivision
3 bed 2 bath 1,082 sqft Built 2006
Raw Value $348,773
Adjusted Value $321,189

Adjusted -$20,049 for 68 sqft less living space and -$7,535 for being older. Net adjustment: -$27,584.

The Neighborhood

This home is valued 9.0% 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

typical
135 Properties
$311,433 Median Value
-11.3% YoY Change
1% Have Pool
100% Have Garage
This Home
$339,447
Median
$311,433

This home is +9.0% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,108 across all districts. With a homestead exemption claimed, that drops to $4,795 — saving $1,313 per year. That's $400 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%$3,032
Round RockCity0.3720%$1,263
Williamson CountyCounty0.3694%$1,254
Austin Community Collegespecial0.1034%$351
Williamson County FM/RdCounty0.0443%$150
Upper Brushy Creek WCIDWater0.0170%$58
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,108

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $321,189 would pay approximately $2,005 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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