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5816 CASSTELLO DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,874 sqftBuilt 2017

Property at a Glance

This home is estimated between $355,337 and $429,651, with a best estimate of $383,144. That places the property below the H123414C - SIENA LIMMER LOOP median of $417,399, in a neighborhood that declined 2.7% over the past year.

Estimated Value Range

$355,337 $429,651
Best Estimate
$383,144
WCAD Value
$376,474
Low Confidence

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

There are 5 comparable properties within range, but none are in H123414C - SIENA LIMMER LOOP. The estimated range of $355,337 and $429,651 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 1,840 sqft Built 2007
Raw Value $406,093
Adjusted Value $429,651

Adjusted +$7,126 for 34 sqft more living space and +$16,432 for being newer. Net adjustment: +$23,558.

3 bed 2 bath 1,845 sqft Built 2015
Raw Value $346,483
Adjusted Value $355,847

Adjusted +$6,078 for 29 sqft more living space and +$3,286 for being newer. Net adjustment: +$9,364.

3 bed 2 bath 1,706 sqft Built 2017
Raw Value $347,933
Adjusted Value $383,144

Adjusted +$35,211 for 168 sqft more living space. Net adjustment: +$35,211.

3 bed 2 bath 1,855 sqft Built 2015
Raw Value $348,069
Adjusted Value $355,337

Adjusted +$3,982 for 19 sqft more living space and +$3,286 for being newer. Net adjustment: +$7,268.

3 bed 2 bath 1,775 sqft Built 2010
Raw Value $376,561
Adjusted Value $408,812

Adjusted +$20,749 for 99 sqft more living space and +$11,502 for being newer. Net adjustment: +$32,251.

The Neighborhood

This home is valued 9.8% below the H123414C - SIENA LIMMER LOOP median of $417,399. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 2.7% over the past year.

H123414C - SIENA LIMMER LOOP

typical
1,146 Properties
$417,399 Median Value
-2.7% YoY Change
0% Have Pool
100% Have Garage
This Home
$376,474
Median
$417,399

This home is -9.8% below the subdivision median.

Tax Analysis

The estimated annual property tax is $8,956 across all districts. With a homestead exemption claimed, that drops to $7,199 — saving $1,757 per year. That's $600 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%$4,537
Siena MUD #2MUD0.6020%$2,266
Williamson CountyCounty0.3694%$1,391
Williamson County ESD #3 - HuttoESD0.1000%$376
Williamson County FM/RdCounty0.0443%$167
EWC Higher Ed Centerspecial0.0409%$154
Upper Brushy Creek WCIDWater0.0170%$64
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.3788%$8,956

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $383,144 would pay approximately $2,392 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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