At $1,411 per month, Zillow’s ZIP-level ZORI for 78748 shows a 4.16% year-over-year decline. ZORI is a typical observed asking-rent index blended across rental types, rather than a lease-specific quote, an occupied-home rent measure, or a bedroom-specific observation. The five-digit label is both a Zillow ZIP market identifier and a Census ZCTA match; a ZCTA is a statistical area and is not identical to a USPS delivery ZIP. That geographic distinction matters because the rent index, survey profile, and administrative standards below use different evidence universes even when they share the same label.
The recent rent direction is negative across the shorter historical windows. Exact same-month annualized ZORI changes were -4.16% over 1 year and -4.13% over 3 years, while the 5-year change was a near-flat 0.11% gain. Thus, the latest decline confirms the three-year weakening path but breaks from the essentially level longer record. Annualized monthly-return variability of 2.74% indicates that individual monthly readings have moved enough to warrant less confidence in one current snapshot than in the broader trend. Separately, the 15.68% maximum drawdown records the largest historical peak-to-trough setback. Coverage was 100%; the transparent national discovery ranks among history-eligible ZIPs were 2,894 for momentum, 1,139 for stability, and 2,577 for the balanced measure. These are backward-looking measurements, not forecasts or investment recommendations.
The ACS evidence answers a different question. In the matched Census ZCTA, the ACS five-year survey places median gross rent for occupied renter homes at $1,839; gross rent includes selected utilities. The current asking-rent index is 76.7% of that survey median, a gap that should not be treated as a contradiction because timing, renter occupancy, utility treatment, and rental composition differ. HUD’s bedroom-specific Fair Market Rent or Small Area Fair Market Rent standard is administrative rather than asking rent: its local two-bedroom standard is $1,852, and current ZORI equals 76.2% of that benchmark. Neither ACS gross rent nor HUD’s standard is a direct asking-rent comparable.
The bedroom series translates the ZIP ZORI through the local HUD ladder, producing modelled monthly estimates rather than measured bedroom rents. The modelled ladder is $1,123 for a studio, $1,190 for one bedroom, $1,411 for two bedrooms, $1,788 for three bedrooms, and $2,103 for four bedrooms. It is useful for showing relative bedroom scaling inside the same ZIP-level rent signal, but it does not establish the asking rent of a particular unit. Applying a 30% rent-to-income screen to the current ZORI produces required annual household income of $56,440. That is arithmetic, not advice and not an applicant qualification rule; the ZCTA median household income is $115,213, while household incomes and lease costs vary materially within any statistical area.
Rent burden and vacancy reinforce the need to avoid treating averages as unit-level outcomes. The ACS survey reports 10,919 renter-occupied homes, with 4,963 renter households paying 30% or more of income toward gross rent, a 45.5% burden share. That measure includes occupied renters and selected utilities, so it is not evidence that any vacant or newly listed home is affordable to a particular household. The ZCTA contains 26,420 housing units and a 4.5% overall vacancy rate. Its structure mix includes 17,303 single-family units and 4,213 units in large multifamily buildings, demonstrating a mixed housing stock rather than a uniform rental product.
Wider-area context places the ZIP’s current asking-rent index below several broader reference points: the Austin city context rent is $1,615, the Travis County context rent is $1,649, and the Austin-Round Rock-Georgetown, TX metro context rent is $1,653. Each is context for a larger named geography, not a substitute ZIP rent observation. The comparison is directionally consistent with the ZIP’s lower current ZORI, but it cannot identify whether the difference reflects unit sizes, property types, listing mix, survey design, or any other unobserved component. The ZIP-level measures remain the relevant evidence for this label.
For-sale conditions present a related but separate tension. Redfin’s direct rolling-three-month ZIP resale observation reports a $408,908 median sold price, down 6.0% year over year, with 161 homes sold and a median 42 days on market. Inventory was 202 homes, and months of supply stood at 3.8. The average sale-to-list ratio was 98.6%, while 19.1% of sales closed above list price. This is resale-market evidence, not rental transaction data. The resale price decline confirms the same broad downward direction seen in recent asking-rent history, yet the sales volume, supply, and sale-to-list signals show that the resale picture is not reducible to the rent decline alone. Annualized ZIP ZORI divided by median sold price is 4.14%, a cross-source screening ratio only, not a cap rate, net return, expected return, or property yield.
The evidence has clear limits. ZORI does not provide unit condition, concessions, utilities, lease length, availability date, or bedroom and bathroom configuration; ACS describes surveyed occupied renter homes rather than current listings; HUD standards are administrative; and Redfin describes resale activity rather than rental economics. A property-level review would therefore need the actual advertised rent, included utilities, fees, concessions, lease terms, bedroom count, condition, and current availability before connecting a unit to these ZIP-level signals. It would also need sale evidence specific to the property if resale is relevant. The central question is whether a particular unit’s verified terms resemble the index and modelled ladder, rather than whether any one aggregate measure can stand in for it.