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3738 CASTLE ROCK DR, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath947 sqftBuilt 2003

Property at a Glance

This home is estimated between $94,579 and $457,845, with a best estimate of $222,017. That places the property below the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194, in a neighborhood that declined 10.9% over the past year.

Estimated Value Range

$94,579 $457,845
Best Estimate
$222,017
WCAD Value
$422,934
Low Confidence

Based on 5 comparable properties(0 in the same subdivision)

There are 5 comparable properties within range, but none are in R107503F - PRESERVE AT STONE OAK - PH 3 & 4. The estimated range of $94,579 and $457,845 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 940 sqft Built 2002
Raw Value $457,821
Adjusted Value $457,845

Adjusted +$1,425 for 7 sqft more living space and -$1,401 for being older. Net adjustment: +$24.

3 bed 1,232 sqft Built 2011
Raw Value $141,391
Adjusted Value $94,579

Adjusted -$58,018 for 285 sqft less living space and +$11,206 for being newer. Net adjustment: -$46,812.

4 bed 2 bath 1,186 sqft Built 1994
Raw Value $407,186
Adjusted Value $345,925

Adjusted -$48,654 for 239 sqft less living space and -$12,607 for being older. Net adjustment: -$61,261.

3 bed 2 bath 1,133 sqft Built 1979
Raw Value $293,501
Adjusted Value $222,017

Adjusted -$37,865 for 186 sqft less living space and -$33,619 for being older. Net adjustment: -$71,484.

3 bed 2 bath 1,212 sqft Built 1982
Raw Value $268,403
Adjusted Value $185,040

Adjusted -$53,947 for 265 sqft less living space and -$29,416 for being older. Net adjustment: -$83,363.

The Neighborhood

This home is valued 14.9% above the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194. With 1,045 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 10.9% over the past year.

R107503F - PRESERVE AT STONE OAK - PH 3 & 4

typical
1,045 Properties
$368,194 Median Value
-10.9% YoY Change
1% Have Pool
99% Have Garage
This Home
$422,934
Median
$368,194

This home is +14.9% above the subdivision median.

Tax Analysis

The estimated annual property tax is $7,610 across all districts. With a homestead exemption claimed, that drops to $6,281 — saving $1,329 per year. That's $523 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%$3,777
Round RockCity0.3720%$1,573
Williamson CountyCounty0.3694%$1,563
Austin Community Collegespecial0.1034%$437
Williamson County FM/RdCounty0.0443%$187
Upper Brushy Creek WCIDWater0.0170%$72
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$7,610

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $222,017 would pay approximately $1,386 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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