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128 GENNAKER DR, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath2,253 sqftBuilt 2017

Property at a Glance

This home is estimated between $695,465 and $1,090,336, with a best estimate of $876,047. That places the property above the R302609C - HIGHLAND HORIZON median of $781,434, in a neighborhood that appreciated 2.3% over the past year.

Estimated Value Range

$695,465 $1,090,336
Best Estimate
$876,047
WCAD Value
$882,543
Low Confidence

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

There are 5 comparable properties within range, but none are in R302609C - HIGHLAND HORIZON. The estimated range of $695,465 and $1,090,336 should be treated as a rough guide.

Comparable Properties (5)

4 bed 3 bath 2,219 sqft Built 2007
Raw Value $904,649
Adjusted Value $1,039,535

Adjusted +$10,517 for 34 sqft more living space and +$124,369 for being newer. Net adjustment: +$134,886.

4 bed 3 bath 1,916 sqft Built 2016
Raw Value $578,786
Adjusted Value $695,465

Adjusted +$104,242 for 337 sqft more living space and +$12,437 for being newer. Net adjustment: +$116,679.

4 bed 3 bath 1,916 sqft Built 2014
Raw Value $562,011
Adjusted Value $703,564

Adjusted +$104,242 for 337 sqft more living space and +$37,311 for being newer. Net adjustment: +$141,553.

4 bed 3 bath 2,154 sqft Built 2001
Raw Value $860,722
Adjusted Value $1,090,336

Adjusted +$30,623 for 99 sqft more living space and +$198,991 for being newer. Net adjustment: +$229,614.

4 bed 3 bath 1,811 sqft Built 2014
Raw Value $702,015
Adjusted Value $876,047

Adjusted +$136,721 for 442 sqft more living space and +$37,311 for being newer. Net adjustment: +$174,032.

The Neighborhood

This home is valued 12.9% above the R302609C - HIGHLAND HORIZON median of $781,434. With 399 homes in the subdivision, the property sits in the upper tier. The neighborhood appreciated 2.3% over the past year.

R302609C - HIGHLAND HORIZON

typical
399 Properties
$781,434 Median Value
+2.3% YoY Change
0% Have Pool
100% Have Garage
This Home
$882,543
Median
$781,434

This home is +12.9% above the subdivision median.

Tax Analysis

The estimated annual property tax is $16,883 across all districts. With a homestead exemption claimed, that drops to $15,477 — saving $1,406 per year. That's $1,290 per month a buyer should budget. The assessed value increased +15.2% vs the subdivision average of +2.3%. This above-average increase gives a protest opportunity score of 95 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$7,524
Brushy Creek MUDMUD0.3868%$3,259
Williamson CountyCounty0.3694%$3,112
Austin Community Collegespecial0.1034%$871
Williamson County ESD #2 - Sam Bass VFDESD0.1000%$842
Brushy Creek MUD Defined AreaMUD0.0900%$758
Williamson County FM/RdCounty0.0443%$373
Upper Brushy Creek WCIDWater0.0170%$143
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0041%$16,883
95 / 100

There may be a strong case to protest this appraisal.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $876,047 would pay approximately $5,468 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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