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5866 CASSTELLO DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath1,791 sqftBuilt 2015

Property at a Glance

This home is estimated between $334,655 and $408,968, with a best estimate of $362,462. 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

$334,655 $408,968
Best Estimate
$362,462
WCAD Value
$368,099
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 $334,655 and $408,968 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 $408,968

Adjusted -$10,270 for 49 sqft less living space and +$13,145 for being newer. Net adjustment: +$2,875.

3 bed 2 bath 1,845 sqft Built 2015
Raw Value $346,483
Adjusted Value $335,165

Adjusted -$11,318 for 54 sqft less living space. Net adjustment: -$11,318.

3 bed 2 bath 1,706 sqft Built 2017
Raw Value $347,933
Adjusted Value $362,462

Adjusted +$17,815 for 85 sqft more living space and -$3,286 for being older. Net adjustment: +$14,529.

3 bed 2 bath 1,855 sqft Built 2015
Raw Value $348,069
Adjusted Value $334,655

Adjusted -$13,414 for 64 sqft less living space. Net adjustment: -$13,414.

3 bed 2 bath 1,775 sqft Built 2010
Raw Value $376,561
Adjusted Value $388,130

Adjusted +$3,353 for 16 sqft more living space and +$8,216 for being newer. Net adjustment: +$11,569.

The Neighborhood

This home is valued 11.8% 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
$368,099
Median
$417,399

This home is -11.8% below the subdivision median.

Tax Analysis

The estimated annual property tax is $8,757 across all districts. With a homestead exemption claimed, that drops to $7,001 — saving $1,756 per year. That's $583 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%$4,436
Siena MUD #2MUD0.6020%$2,216
Williamson CountyCounty0.3694%$1,360
Williamson County ESD #3 - HuttoESD0.1000%$368
Williamson County FM/RdCounty0.0443%$163
EWC Higher Ed Centerspecial0.0409%$150
Upper Brushy Creek WCIDWater0.0170%$63
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.3788%$8,757

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $362,462 would pay approximately $2,262 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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