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3800 SPYGLASS CV, ROUND ROCK, TX 78664

ROUND ROCK, 78664 — williamson County

3 bed2 bath2,180 sqftBuilt 2004

Property at a Glance

This home is estimated between $321,241 and $630,908, with a best estimate of $573,100. That places the property above the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276, in a neighborhood that declined 8.7% over the past year.

Estimated Value Range

$321,241 $630,908
Best Estimate
$573,100
WCAD Value
$447,589
High Confidence

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

Based on 5 comparable properties in R550600D - Forest Creek Sec 15,16,19,31, this home's estimated market value is between $321,241 and $630,908. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

3802 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2 bath 1,634 sqft Built 2004
Raw Value $474,694
Adjusted Value $630,908

Adjusted +$156,214 for 546 sqft more living space. Net adjustment: +$156,214.

3804 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 2,013 sqft Built 2004
Raw Value $525,320
Adjusted Value $573,100

Adjusted +$47,780 for 167 sqft more living space. Net adjustment: +$47,780.

3810 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 3,073 sqft Built 2005
Raw Value $578,699
Adjusted Value $321,241

Adjusted -$255,493 for 893 sqft less living space and -$1,965 for being older. Net adjustment: -$257,458.

3803 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
3 bed 2 bath 2,527 sqft Built 2003
Raw Value $491,158
Adjusted Value $393,844

Adjusted -$99,279 for 347 sqft less living space and +$1,965 for being newer. Net adjustment: -$97,314.

3809 SPYGLASS CV, ROUND ROCK, TX 78664
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,146 sqft Built 2005
Raw Value $595,480
Adjusted Value $603,243

Adjusted +$9,728 for 34 sqft more living space and -$1,965 for being older. Net adjustment: +$7,763.

The Neighborhood

This home is valued 13.0% below the R550600D - Forest Creek Sec 15,16,19,31 median of $514,276. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 8.7% over the past year.

R550600D - Forest Creek Sec 15,16,19,31

typical
274 Properties
$514,276 Median Value
-8.7% YoY Change
0% Have Pool
99% Have Garage
This Home
$447,589
Median
$514,276

This home is -13.0% below the subdivision median.

Tax Analysis

The estimated annual property tax is $8,053 across all districts. With a homestead exemption claimed, that drops to $6,720 — saving $1,333 per year. That's $560 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
Round Rock ISDSchool0.8931%$3,997
Round RockCity0.3720%$1,665
Williamson CountyCounty0.3694%$1,654
Austin Community Collegespecial0.1034%$463
Williamson County FM/RdCounty0.0443%$198
Upper Brushy Creek WCIDWater0.0170%$76
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$8,053

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $573,100 would pay approximately $3,577 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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