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3921 BLUE MONSTER CV, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed2 bath2,146 sqftBuilt 2002

Property at a Glance

This home is estimated between $335,306 and $744,579, with a best estimate of $529,731. That places the property above the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276, in a neighborhood that declined 8.7% over the past year.

Estimated Value Range

$335,306 $744,579
Best Estimate
$529,731
WCAD Value
$439,090
High Confidence

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

Based on 5 comparable properties in R550600D - Forest Creek Sec 15,16,19,31, this home's estimated market value is between $335,306 and $744,579. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3910 BLUE MONSTER CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,927 sqft Built 2002
Raw Value $467,074
Adjusted Value $529,731

Adjusted +$62,657 for 219 sqft more living space. Net adjustment: +$62,657.

3904 BLUE MONSTER CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 3 bath 1,830 sqft Built 2001
Raw Value $527,060
Adjusted Value $619,435

Adjusted +$90,410 for 316 sqft more living space and +$1,965 for being newer. Net adjustment: +$92,375.

3928 BLUE MONSTER CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,510 sqft Built 2003
Raw Value $564,580
Adjusted Value $744,579

Adjusted +$181,964 for 636 sqft more living space and -$1,965 for being older. Net adjustment: +$179,999.

3909 BLUE MONSTER CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2 bath 2,779 sqft Built 2002
Raw Value $516,411
Adjusted Value $335,306

Adjusted -$181,105 for 633 sqft less living space. Net adjustment: -$181,105.

3908 BLUE MONSTER CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,494 sqft Built 2002
Raw Value $485,163
Adjusted Value $385,598

Adjusted -$99,565 for 348 sqft less living space. Net adjustment: -$99,565.

The Neighborhood

This home is valued 14.6% below the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 8.7% over the past year.

R550600D - Forest Creek Sec 15,16,19,31

typical
274 Properties
$514,276 Median Value
-8.7% YoY Change
0% Have Pool
99% Have Garage
This Home
$439,090
Median
$514,276

This home is -14.6% below the subdivision median.

Tax Analysis

The estimated annual property tax is $7,900 across all districts. With a homestead exemption claimed, that drops to $6,569 — saving $1,331 per year. That's $547 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%$3,922
Round RockCity0.3720%$1,633
Williamson CountyCounty0.3694%$1,622
Austin Community Collegespecial0.1034%$454
Williamson County FM/RdCounty0.0443%$195
Upper Brushy Creek WCIDWater0.0170%$75
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$7,900

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $529,731 would pay approximately $3,307 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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