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521 KOLBO DR, ROUND ROCK, TX 78665

ROUND ROCK, 78665 — williamson County

4 bed3 bath1,592 sqftBuilt 2018

Property at a Glance

This home is estimated between $580,946 and $751,855, with a best estimate of $680,776. That places the property below the R500515C - FOREST GROVE median of $686,297, in a neighborhood that declined 2.9% over the past year.

Estimated Value Range

$580,946 $751,855
Best Estimate
$680,776
WCAD Value
$614,875
High Confidence

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

Based on 5 comparable properties in R500515C - FOREST GROVE, this home's estimated market value is between $580,946 and $751,855. All 5 comparables are in the same subdivision, giving this estimate high confidence.

Comparable Properties (5)

524 KOLBO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
5 bed 3 bath 1,947 sqft Built 2018
Raw Value $775,066
Adjusted Value $680,776

Adjusted -$94,290 for 355 sqft less living space. Net adjustment: -$94,290.

516 KOLBO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
5 bed 3 bath 1,925 sqft Built 2018
Raw Value $670,242
Adjusted Value $581,796

Adjusted -$88,446 for 333 sqft less living space. Net adjustment: -$88,446.

608 KOLBO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
4 bed 3 bath 2,253 sqft Built 2018
Raw Value $756,510
Adjusted Value $580,946

Adjusted -$175,564 for 661 sqft less living space. Net adjustment: -$175,564.

600 KOLBO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
3 bed 2 bath 1,425 sqft Built 2018
Raw Value $707,499
Adjusted Value $751,855

Adjusted +$44,356 for 167 sqft more living space. Net adjustment: +$44,356.

536 KOLBO DR, ROUND ROCK, TX 78665
0.00 mi 100% similar Same subdivision
4 bed 3 bath 1,909 sqft Built 2018
Raw Value $768,825
Adjusted Value $684,628

Adjusted -$84,197 for 317 sqft less living space. Net adjustment: -$84,197.

The Neighborhood

This home is valued 10.4% below the R500515C - FOREST GROVE median of $686,297. That positions it competitively for buyers comparing within the neighborhood. Note that values in this subdivision declined 2.9% over the past year.

R500515C - FOREST GROVE

typical
197 Properties
$686,297 Median Value
-2.9% YoY Change
1% Have Pool
100% Have Garage
This Home
$614,875
Median
$686,297

This home is -10.4% below the subdivision median.

Tax Analysis

The estimated annual property tax is $11,063 across all districts. With a homestead exemption claimed, that drops to $9,699 — saving $1,364 per year. That's $808 per month a buyer should budget. The assessed value increased +4.3% vs the subdivision average of -2.9%. This above-average increase gives a protest opportunity score of 46 out of 100 — it may be worth challenging the appraisal.

Tax Districts

DistrictTypeRateAnnual Amount
Round Rock ISDSchool0.8931%$5,491
Round RockCity0.3720%$2,287
Williamson CountyCounty0.3694%$2,272
Austin Community Collegespecial0.1034%$636
Williamson County FM/RdCounty0.0443%$273
Upper Brushy Creek WCIDWater0.0170%$105
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.7993%$11,063
46 / 100

Moderate opportunity to protest.

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $680,776 would pay approximately $4,249 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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