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121 GENNAKER DR, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath2,006 sqftBuilt 2015

Property at a Glance

This home is estimated between $594,188 and $989,059, with a best estimate of $774,770. That places the property below the R302609C - HIGHLAND HORIZON median of $781,434, in a neighborhood that appreciated 2.3% over the past year.

Estimated Value Range

$594,188 $989,059
Best Estimate
$774,770
WCAD Value
$798,783
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 $594,188 and $989,059 should be treated as a rough guide.

Comparable Properties (5)

4 bed 3 bath 1,916 sqft Built 2014
Raw Value $562,011
Adjusted Value $602,287

Adjusted +$27,839 for 90 sqft more living space and +$12,437 for being newer. Net adjustment: +$40,276.

4 bed 3 bath 1,916 sqft Built 2016
Raw Value $578,786
Adjusted Value $594,188

Adjusted +$27,839 for 90 sqft more living space and -$12,437 for being older. Net adjustment: +$15,402.

4 bed 3 bath 1,811 sqft Built 2014
Raw Value $702,015
Adjusted Value $774,770

Adjusted +$60,318 for 195 sqft more living space and +$12,437 for being newer. Net adjustment: +$72,755.

4 bed 3 bath 2,219 sqft Built 2007
Raw Value $904,649
Adjusted Value $938,259

Adjusted -$65,886 for 213 sqft less living space and +$99,496 for being newer. Net adjustment: +$33,610.

4 bed 3 bath 2,154 sqft Built 2001
Raw Value $860,722
Adjusted Value $989,059

Adjusted -$45,780 for 148 sqft less living space and +$174,117 for being newer. Net adjustment: +$128,337.

The Neighborhood

This home is valued 2.2% 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
$798,783
Median
$781,434

This home is +2.2% above the subdivision median.

Tax Analysis

The estimated annual property tax is $16,009 across all districts. With a homestead exemption claimed, that drops to $14,611 — saving $1,398 per year. That's $1,218 per month a buyer should budget. The assessed value increased +8.8% vs the subdivision average of +2.3%. This above-average increase gives a protest opportunity score of 53 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$7,134
Brushy Creek MUDMUD0.3868%$3,090
Williamson CountyCounty0.3694%$2,951
Austin Community Collegespecial0.1034%$826
Williamson County ESD #2 - Sam Bass VFDESD0.1000%$799
Brushy Creek MUD Defined AreaMUD0.0900%$719
Williamson County FM/RdCounty0.0443%$354
Upper Brushy Creek WCIDWater0.0170%$136
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.0041%$16,009
53 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $774,770 would pay approximately $4,836 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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