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3771 CASTLE ROCK DR, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath1,536 sqftBuilt 2005

Property at a Glance

This home is estimated between $211,682 and $362,700, with a best estimate of $334,665. 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

$211,682 $362,700
Best Estimate
$334,665
WCAD Value
$312,486
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 $211,682 and $362,700 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 1,585 sqft Built 1997
Raw Value $383,881
Adjusted Value $362,700

Adjusted -$9,975 for 49 sqft less living space and -$11,206 for being older. Net adjustment: -$21,181.

3 bed 2 bath 1,584 sqft Built 1995
Raw Value $381,657
Adjusted Value $357,877

Adjusted -$9,772 for 48 sqft less living space and -$14,008 for being older. Net adjustment: -$23,780.

3 bed 2 bath 1,675 sqft Built 1995
Raw Value $367,941
Adjusted Value $325,636

Adjusted -$28,297 for 139 sqft less living space and -$14,008 for being older. Net adjustment: -$42,305.

3 bed 2 bath 1,550 sqft Built 1984
Raw Value $366,931
Adjusted Value $334,665

Adjusted -$2,850 for 14 sqft less living space and -$29,416 for being older. Net adjustment: -$32,266.

3 bed 1,232 sqft Built 2011
Raw Value $141,391
Adjusted Value $211,682

Adjusted +$61,886 for 304 sqft more living space and +$8,405 for being newer. Net adjustment: +$70,291.

The Neighborhood

This home is valued 15.1% below the R107503F - PRESERVE AT STONE OAK - PH 3 & 4 median of $368,194. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 10.9% over the past year.

R107503F - PRESERVE AT STONE OAK - PH 3 & 4

below average
1,045 Properties
$368,194 Median Value
-10.9% YoY Change
1% Have Pool
99% Have Garage
This Home
$312,486
Median
$368,194

This home is -15.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $5,622 across all districts. With a homestead exemption claimed, that drops to $4,314 — saving $1,308 per year. That's $360 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%$2,791
Round RockCity0.3720%$1,162
Williamson CountyCounty0.3694%$1,154
Austin Community Collegespecial0.1034%$323
Williamson County FM/RdCounty0.0443%$139
Upper Brushy Creek WCIDWater0.0170%$53
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$5,622

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $334,665 would pay approximately $2,089 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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