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4285 CR 123, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

2 bed816 sqftBuilt 1929

Property at a Glance

This home is estimated between $308,218 and $567,973, with a best estimate of $389,983. That places the property above the H308403H - CENTRAL SOUTH OF 79 median of $306,864, in a neighborhood that declined 5.9% over the past year.

Estimated Value Range

$308,218 $567,973
Best Estimate
$389,983
WCAD Value
$4,647,594
Low Confidence

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

There are 5 comparable properties within range, but none are in H308403H - CENTRAL SOUTH OF 79. The estimated range of $308,218 and $567,973 should be treated as a rough guide.

Comparable Properties (5)

2 bed 1 bath 824 sqft Built 1984
Raw Value $228,462
Adjusted Value $416,859

Adjusted -$1,539 for 8 sqft less living space and +$243,599 for being newer and -$53,663 for no garage. Net adjustment: +$188,397.

2 bed 1 bath 865 sqft Built 1982
Raw Value $218,331
Adjusted Value $389,983

Adjusted -$9,426 for 49 sqft less living space and +$234,741 for being newer and -$53,663 for no garage. Net adjustment: +$171,652.

2 bed 1 bath 808 sqft Built 1950
Raw Value $213,668
Adjusted Value $308,218

Adjusted +$1,539 for 8 sqft more living space and +$93,011 for being newer. Net adjustment: +$94,550.

3 bed 2 bath 884 sqft Built 2003
Raw Value $306,965
Adjusted Value $567,973

Adjusted -$13,081 for 68 sqft less living space and +$327,752 for being newer and -$53,663 for no garage. Net adjustment: +$261,008.

2 bed 2 bath 1,070 sqft Built 1984
Raw Value $229,494
Adjusted Value $370,570

Adjusted -$48,860 for 254 sqft less living space and +$243,599 for being newer and -$53,663 for no garage. Net adjustment: +$141,076.

The Neighborhood

This home is valued 1414.5% above the H308403H - CENTRAL SOUTH OF 79 median of $306,864. With 1,570 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 5.9% over the past year.

H308403H - CENTRAL SOUTH OF 79

outlier high
1,570 Properties
$306,864 Median Value
-5.9% YoY Change
1% Have Pool
98% Have Garage
This Home
$4,647,594
Median
$306,864

This home is +1414.5% above the subdivision median.

Tax Analysis

The estimated annual property tax is $4,186 across all districts. With a homestead exemption claimed, that drops to $2,455 — saving $1,731 per year. That's $205 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
Hutto ISDSchool1.2052%$2,839
Williamson CountyCounty0.3694%$870
Williamson County ESD #9 - Round RockESD0.0999%$235
Williamson County FM/RdCounty0.0443%$104
EWC Higher Ed Centerspecial0.0409%$96
Upper Brushy Creek WCIDWater0.0170%$40
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7768%$4,186

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $389,983 would pay approximately $2,434 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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