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509 KAROLYN DR, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed2 bath1,632 sqftBuilt 1985

Property at a Glance

This home is estimated between $293,911 and $360,364, with a best estimate of $329,919. That places the property below the R462475H - Egger Acres median of $353,946, in a neighborhood that declined 4.4% over the past year.

Estimated Value Range

$293,911 $360,364
Best Estimate
$329,919
WCAD Value
$382,000
Medium Confidence

Based on 5 comparable properties(3 in the same subdivision)

Based on 5 comparable properties (3 in the same subdivision, 2 nearby), the estimated range is $293,911 and $360,364. More comparables in the same subdivision would strengthen this estimate.

Comparable Properties (5)

608 KAROLYN DR, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,006 sqft Built 1975
Raw Value $379,361
Adjusted Value $293,911

Adjusted -$81,278 for 374 sqft less living space and -$4,172 for being older. Net adjustment: -$85,450.

602 VIRGINIA DR, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,884 sqft Built 1970
Raw Value $379,486
Adjusted Value $318,463

Adjusted -$54,765 for 252 sqft less living space and -$6,258 for being older. Net adjustment: -$61,023.

3 bed 2 bath 1,474 sqft Built 1985
Raw Value $304,858
Adjusted Value $339,195

Adjusted +$34,337 for 158 sqft more living space. Net adjustment: +$34,337.

3 bed 2 bath 1,830 sqft Built 1983
Raw Value $373,783
Adjusted Value $329,919

Adjusted -$43,030 for 198 sqft less living space and -$834 for being older. Net adjustment: -$43,864.

516 VIRGINIA DR, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,447 sqft Built 1970
Raw Value $326,418
Adjusted Value $360,364

Adjusted +$40,204 for 185 sqft more living space and -$6,258 for being older. Net adjustment: +$33,946.

The Neighborhood

This home is valued 7.9% above the R462475H - Egger Acres median of $353,946. With 340 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 4.4% over the past year.

R462475H - Egger Acres

typical
340 Properties
$353,946 Median Value
-4.4% YoY Change
6% Have Pool
87% Have Garage
This Home
$382,000
Median
$353,946

This home is +7.9% above the subdivision median.

Tax Analysis

The estimated annual property tax is $6,873 across all districts. With a homestead exemption claimed, that drops to $5,552 — saving $1,321 per year. That's $463 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%$3,412
Round RockCity0.3720%$1,421
Williamson CountyCounty0.3694%$1,411
Austin Community Collegespecial0.1034%$395
Williamson County FM/RdCounty0.0443%$169
Upper Brushy Creek WCIDWater0.0170%$65
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$6,873

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $329,919 would pay approximately $2,059 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 4/19/2026.

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