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506/508 SIERRA CV, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed4 bath2,048 sqftBuilt 1984

Property at a Glance

This home is estimated between $360,843 and $485,113, with a best estimate of $413,774. That places the property above the R450X - Round Rock East - Duplex median of $355,449, in a neighborhood that declined 8.7% over the past year.

Estimated Value Range

$360,843 $485,113
Best Estimate
$413,774
WCAD Value
$360,633
High Confidence

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

Based on 5 comparable properties in R450X - Round Rock East - Duplex, this home's estimated market value is between $360,843 and $485,113. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

501/503 SIERRA CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 4 bath 1,586 sqft Built 1984
Raw Value $324,502
Adjusted Value $414,274

Adjusted +$89,772 for 462 sqft more living space. Net adjustment: +$89,772.

1600 VILLA CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
5 bed 4 bath 1,652 sqft Built 1979
Raw Value $403,164
Adjusted Value $485,113

Adjusted +$76,948 for 396 sqft more living space and +$5,001 for being newer. Net adjustment: +$81,949.

509/511 SIERRA CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 4 bath 1,815 sqft Built 1984
Raw Value $339,475
Adjusted Value $384,750

Adjusted +$45,275 for 233 sqft more living space. Net adjustment: +$45,275.

502/504 SIERRA CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 4 bath 1,586 sqft Built 1984
Raw Value $324,002
Adjusted Value $413,774

Adjusted +$89,772 for 462 sqft more living space. Net adjustment: +$89,772.

505/507 SIERRA CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 4 bath 2,048 sqft Built 1984
Raw Value $360,843
Adjusted Value $360,843

This comparable closely matches the subject property's features.

The Neighborhood

This home is valued 1.5% above the R450X - Round Rock East - Duplex median of $355,449. With 836 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 8.7% over the past year.

R450X - Round Rock East - Duplex

typical
836 Properties
$355,449 Median Value
-8.7% YoY Change
0% Have Pool
84% Have Garage
This Home
$360,633
Median
$355,449

This home is +1.5% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,489 across all districts. With a homestead exemption claimed, that drops to $5,172 — saving $1,317 per year. That's $431 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%$3,221
Round RockCity0.3720%$1,342
Williamson CountyCounty0.3694%$1,332
Austin Community Collegespecial0.1034%$373
Williamson County FM/RdCounty0.0443%$160
Upper Brushy Creek WCIDWater0.0170%$61
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,489

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $413,774 would pay approximately $2,583 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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