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5850 CASSTELLO DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

3 bed2 bath2,317 sqftBuilt 2016

Property at a Glance

This home is estimated between $373,037 and $479,987, with a best estimate of $457,310. That places the property above the H123414C - SIENA LIMMER LOOP median of $417,399, in a neighborhood that declined 2.7% over the past year.

Estimated Value Range

$373,037 $479,987
Best Estimate
$457,310
WCAD Value
$431,078
Low Confidence

Based on 5 comparable properties(2 in the same subdivision)

There are 5 comparable properties within range, but few are in H123414C - SIENA LIMMER LOOP. The estimated range of $373,037 and $479,987 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 2,208 sqft Built 2014
Raw Value $431,179
Adjusted Value $457,310

Adjusted +$22,845 for 109 sqft more living space and +$3,286 for being newer. Net adjustment: +$26,131.

3 bed 2 bath 2,448 sqft Built 2017
Raw Value $421,647
Adjusted Value $392,548

Adjusted -$27,456 for 131 sqft less living space and -$1,643 for being older. Net adjustment: -$29,099.

5866 CASSTELLO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,791 sqft Built 2015
Raw Value $368,099
Adjusted Value $479,987

Adjusted +$110,245 for 526 sqft more living space and +$1,643 for being newer. Net adjustment: +$111,888.

6616 LEONARDO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
4 bed 2 bath 2,740 sqft Built 2018
Raw Value $464,980
Adjusted Value $373,037

Adjusted -$88,657 for 423 sqft less living space and -$3,286 for being older. Net adjustment: -$91,943.

3 bed 2 bath 2,305 sqft Built 2007
Raw Value $461,479
Adjusted Value $478,783

Adjusted +$2,515 for 12 sqft more living space and +$14,789 for being newer. Net adjustment: +$17,304.

The Neighborhood

This home is valued 3.3% above the H123414C - SIENA LIMMER LOOP median of $417,399. With 1,146 homes in the subdivision, the property sits in the upper tier. 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
$431,078
Median
$417,399

This home is +3.3% above the subdivision median.

Tax Analysis

The estimated annual property tax is $10,255 across all districts. With a homestead exemption claimed, that drops to $8,488 — saving $1,767 per year. That's $707 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%$5,195
Siena MUD #2MUD0.6020%$2,595
Williamson CountyCounty0.3694%$1,593
Williamson County ESD #3 - HuttoESD0.1000%$431
Williamson County FM/RdCounty0.0443%$191
EWC Higher Ed Centerspecial0.0409%$176
Upper Brushy Creek WCIDWater0.0170%$73
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax2.3788%$10,255

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $457,310 would pay approximately $2,855 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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