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3811 SEBASTIAN CV, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

4 bed3 bath1,650 sqftBuilt 2007

Property at a Glance

This home is estimated between $338,779 and $685,824, with a best estimate of $503,613. That places the property below the L498506D - VILLAGE AT MAYFIELD median of $510,992, in a neighborhood that declined 5.8% over the past year.

Estimated Value Range

$338,779 $685,824
Best Estimate
$503,613
WCAD Value
$558,613
High Confidence

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

Based on 5 comparable properties in L498506D - VILLAGE AT MAYFIELD, this home's estimated market value is between $338,779 and $685,824. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3803 SEBASTIAN CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,868 sqft Built 2005
Raw Value $474,017
Adjusted Value $413,782

Adjusted -$60,776 for 218 sqft less living space and +$541 for being newer. Net adjustment: -$60,235.

3826 SEBASTIAN CV, ROUND ROCK, TX 78681
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,710 sqft Built 2004
Raw Value $544,357
Adjusted Value $528,442

Adjusted -$16,727 for 60 sqft less living space and +$812 for being newer. Net adjustment: -$15,915.

3601 COBALT CV, ROUND ROCK, TX 78681
0.08 mi 100% similar Same subdivision
3 bed 2 bath 1,835 sqft Built 2003
Raw Value $389,272
Adjusted Value $338,779

Adjusted -$51,576 for 185 sqft less living space and +$1,083 for being newer. Net adjustment: -$50,493.

3600 COBALT CV, ROUND ROCK, TX 78681
0.08 mi 100% similar Same subdivision
4 bed 3 bath 1,980 sqft Built 2003
Raw Value $594,530
Adjusted Value $503,613

Adjusted -$92,000 for 330 sqft less living space and +$1,083 for being newer. Net adjustment: -$90,917.

3604 COBALT CV, ROUND ROCK, TX 78681
0.08 mi 100% similar Same subdivision
4 bed 2 bath 1,370 sqft Built 2003
Raw Value $606,680
Adjusted Value $685,824

Adjusted +$78,061 for 280 sqft more living space and +$1,083 for being newer. Net adjustment: +$79,144.

The Neighborhood

This home is valued 9.3% above the L498506D - VILLAGE AT MAYFIELD median of $510,992. With 696 homes in the subdivision, the property sits in the upper tier. Note that values in this subdivision declined 5.8% over the past year.

L498506D - VILLAGE AT MAYFIELD

typical
696 Properties
$510,992 Median Value
-5.8% YoY Change
1% Have Pool
100% Have Garage
This Home
$558,613
Median
$510,992

This home is +9.3% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,051 across all districts. With a homestead exemption claimed, that drops to $8,697 — saving $1,354 per year. That's $725 per month a buyer should budget. The assessed value increased +6.4% vs the subdivision average of -5.8%. This above-average increase gives a protest opportunity score of 65 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$4,989
Round RockCity0.3720%$2,078
Williamson CountyCounty0.3694%$2,064
Austin Community Collegespecial0.1034%$578
Williamson County FM/RdCounty0.0443%$248
Upper Brushy Creek WCIDWater0.0170%$95
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$10,051
65 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $503,613 would pay approximately $3,144 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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