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1800 SUN LAKE, ROUND ROCK, TX 78681

ROUND ROCK, 78681 — williamson County

3 bed2 bath2,598 sqftBuilt 1984

Property at a Glance

This home is estimated between $262,773 and $781,581, with a best estimate of $670,183. That places the property below the R202681C - Tonkawa & Oak Springs median of $851,894, in a neighborhood that appreciated 3.7% over the past year.

Estimated Value Range

$262,773 $781,581
Best Estimate
$670,183
WCAD Value
$621,317
Low Confidence

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

There are 5 comparable properties within range, but none are in R202681C - Tonkawa & Oak Springs. The estimated range of $262,773 and $781,581 should be treated as a rough guide.

Comparable Properties (5)

3 bed 2 bath 2,044 sqft Built 1981
Raw Value $455,252
Adjusted Value $670,183

Adjusted +$192,358 for 554 sqft more living space and +$22,573 for being newer. Net adjustment: +$214,931.

3 bed 2 bath 1,877 sqft Built 1984
Raw Value $405,447
Adjusted Value $655,791

Adjusted +$250,344 for 721 sqft more living space. Net adjustment: +$250,344.

3 bed 2 bath 3,097 sqft Built 2000
Raw Value $556,425
Adjusted Value $262,773

Adjusted -$173,261 for 499 sqft less living space and -$120,391 for being older. Net adjustment: -$293,652.

3 bed 2 bath 1,971 sqft Built 1975
Raw Value $496,156
Adjusted Value $781,581

Adjusted +$217,705 for 627 sqft more living space and +$67,720 for being newer. Net adjustment: +$285,425.

3 bed 2 bath 1,550 sqft Built 1984
Raw Value $366,931
Adjusted Value $730,815

Adjusted +$363,884 for 1,048 sqft more living space. Net adjustment: +$363,884.

The Neighborhood

This home is valued 27.1% below the R202681C - Tonkawa & Oak Springs median of $851,894. That positions it competitively for buyers comparing within the neighborhood. The neighborhood appreciated 3.7% over the past year.

R202681C - Tonkawa & Oak Springs

below average
154 Properties
$851,894 Median Value
+3.7% YoY Change
7% Have Pool
92% Have Garage
This Home
$621,317
Median
$851,894

This home is -27.1% below the subdivision median.

Tax Analysis

The estimated annual property tax is $9,489 across all districts. With a homestead exemption claimed, that drops to $8,124 — saving $1,365 per year. That's $677 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%$5,549
Williamson CountyCounty0.3694%$2,295
Austin Community Collegespecial0.1034%$642
Williamson County ESD #2 - Sam Bass VFDESD0.1000%$621
Williamson County FM/RdCounty0.0443%$275
Upper Brushy Creek WCIDWater0.0170%$106
Williamson Central Appraisal Districtcad0.0000%$0
Total Annual Tax1.5273%$9,489

Mortgage Context

At today's 30-year mortgage rate of 6.38%, a buyer financing $670,183 would pay approximately $4,183 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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