Technology in appraisals AO 41

[RCA]

God, do you speak nonsense! Zillow does not use RCAs, and they don't even have a "model"! They use a black-box approach that effectively assumes what they don't know is just the average. That is, if they don't know the condition of a home, which they often don't, then they assume it is the average for that property type in its neighborhood. They can't be that accurate, simply because they don't have inspection-level information on most of the homes they value.

In my opinion, you are not much better than the black box, at best. You operate on seat-of-the-pants judgments, which invariably use your subjective observations and patterns you have subjectively picked up over the years. You have nothing much more than a rule that "The price must be somewhere in the neighborhood of homes sold in the past year that are relatively similar to the subject. You fidget around with "matched pairs" to get some dicey adjustments and, in the end, make sure that value looks like it is in the right ballpark. You make many assumptions that, if investigated, might not pan out. I can see where you would easily get in troiuble.

Of course, I only know what I see on this forum. Maybe you are just being sloppy on the forum. I don't know. But from appearances on this forum, I'd be more cautious if I were you.

As far as Zillow's accuracy. Well, let's compare Redfin and Zillow. Grok says they both have about the same accuracy:

Grok: "Based on the most recent official data published by each company, Zillow's Zestimate shows slightly higher accuracy in home price predictions than Redfin's Estimate. This conclusion is drawn from nationwide median error rates, which measure the percentage difference between the estimated value and the actual sale price.

Zillow reports a median error rate of 1.83% for homes actively listed on the market and 7.01% for off-market properties. In contrast, Redfin indicates a median error rate of 2.00% for on-market homes and 7.69% for off-market homes. These figures suggest that Zillow's predictions are marginally closer to actual sale prices, particularly for properties not currently listed.

It is important to note that both tools rely on algorithms that incorporate public data, such as property details, recent sales, and market trends. However, their accuracy can vary by location, property type, and data availability, and neither should substitute for a professional appraisal. Historical comparisons from earlier years sometimes favored Redfin, but current statistics indicate Zillow's edge in precision."

That makes sense, because according to my information, they both use pretty much the same statistical methods.

Now, let me give you an example of a house I am familiar with as a comp or subject: 120 Hillcrest, Berkeley, CA.

Currently
Zillow Estimate: $6,649,400
Redfin Estimate: $4,447,552

Zillow is 50% higher than Redfin. That is as of 1/6/2026.

Fern, from my perspective - you are nothing but a Nut Case. You don't know ****. You don't really know you're own **** - because you are so messed up in your own logic and knowledge.

Do you know why Zillow is somewhat more accurate than Redfin in its estimates of. homes that have been off-market for an extended period? I doubt it. I know the reason.

 

[Fernando]

God, do you speak nonsense! Zillow does not use RCAs, and they don't even have a "model"! They use a black-box approach that effectively assumes what they don't know is just the average. That is, if they don't know the condition of a home, which they often don't, then they assume it is the average for that property type in its neighborhood. They can't be that accurate, simply because they don't have inspection-level information on most of the homes they value.

So your saying that Zillow a $16 billion company would not have the resources to outsmart your limited budget computer model?
Your model is similar to Zillow in that it looks at sales even outside neighborhood boundaries and can't consider market conditions.

In my opinion, you are not much better than the black box, at best. You operate on seat-of-the-pants judgments, which invariably use your subjective observations and patterns you have subjectively picked up over the years. You have nothing much more than a rule that "The price must be somewhere in the neighborhood of homes sold in the past year that are relatively similar to the subject. You fidget around with "matched pairs" to get some dicey adjustments and, in the end, make sure that value looks like it is in the right ballpark. You make many assumptions that, if investigated, might not pan out. I can see where you would easily get in troiuble.

What I have besides experience and intuition in appraising is that I have rental properties and I understand from mindset of buyers and sellers in their decisions in purchases.
Even an MAI with no real estate ownership will not understand this for they just look at the numbers.

Of course, I only know what I see on this forum. Maybe you are just being sloppy on the forum. I don't know. But from appearances on this forum, I'd be more cautious if I were you.

As far as Zillow's accuracy. Well, let's compare Redfin and Zillow. Grok says they both have about the same accuracy:

Grok: "Based on the most recent official data published by each company, Zillow's Zestimate shows slightly higher accuracy in home price predictions than Redfin's Estimate. This conclusion is drawn from nationwide median error rates, which measure the percentage difference between the estimated value and the actual sale price.

What do Grok know. I find Redfin's estimate more accurate than Zillow around here.

Zillow reports a median error rate of 1.83% for homes actively listed on the market and 7.01% for off-market properties. In contrast, Redfin indicates a median error rate of 2.00% for on-market homes and 7.69% for off-market homes. These figures suggest that Zillow's predictions are marginally closer to actual sale prices, particularly for properties not currently listed.

It is important to note that both tools rely on algorithms that incorporate public data, such as property details, recent sales, and market trends. However, their accuracy can vary by location, property type, and data availability, and neither should substitute for a professional appraisal. Historical comparisons from earlier years sometimes favored Redfin, but current statistics indicate Zillow's edge in precision."

That makes sense, because according to my information, they both use pretty much the same statistical methods.

Now, let me give you an example of a house I am familiar with as a comp or subject: 120 Hillcrest, Berkeley, CA.

Currently
Zillow Estimate: $6,649,400
Redfin Estimate: $4,447,552

Zillow is 50% higher than Redfin. That is as of 1/6/2026.

So which is right? Stop throwing numbers and state figures instead of analyzing why they are different.

Fern, from my perspective - you are nothing but a Nut Case. You don't know ****. You don't really know you're own **** - because you are so messed up in your own logic and knowledge.

RCA, from my perspective - you are nothing but a Nut Case because whatever computer model you're chasing, it will not be in practical useful for most appraisers.
The problem with PHD types are that they rarely become rich because their ideas need to be implemented and not just theoretical pursuits.

 

[Fernando]

Rain finally over here today.
So many flooding issues and appraisers should be noting where the problem areas are.
In certain areas especially in Marin county, we learn of areas that were flooded not just from the rain but from high King Tides.
Does FEMA consider King Tides? Even SF had high tide water going onto the embacadero waterfront streets. And SF does not have FEMA maps.
Maybe climate change is real.

 

[Non Sequitur]

Further proof TAF and the AQB are hopelessly behind. While they submit a draft this is what's happening NOW (watch the short video):

People in the mortgage industry have no idea how fast things are about to move I’ve never written a line of code in my life and using AI, I made an entire UAD3.6 compliant appraisal form software in… | Brian Zitin

People in the mortgage industry have no idea how fast things are about to move I’ve never written a line of code in my life and using AI, I made an entire UAD3.6 compliant appraisal form software in THREE DAYS, on the side while doing my day job of being a CEO This is taking legacy incumbents...

www.linkedin.com

 

[TerryRohrer]

Further proof TAF and the AQB are hopelessly behind. While they submit a draft this is what's happening NOW (watch the short video):

People in the mortgage industry have no idea how fast things are about to move I’ve never written a line of code in my life and using AI, I made an entire UAD3.6 compliant appraisal form software in… | Brian Zitin

People in the mortgage industry have no idea how fast things are about to move I’ve never written a line of code in my life and using AI, I made an entire UAD3.6 compliant appraisal form software in THREE DAYS, on the side while doing my day job of being a CEO This is taking legacy incumbents...

www.linkedin.com

Have you test driven it yet?

 

[Non Sequitur]

Have you test driven it yet?

No. But the point is the exposure draft is years behind what’s happening in the world outside of their echo chamber.

 

[Sadie]

Wait a second.....

CubiCasa does not publicly report a specific percentage of error or miss rate for gross living area (GLA) calculations.

However, industry studies referenced in the context indicate that traditional appraisals can show an average 4% difference in GLA between two appraisers, with nearly 5% of properties having GLA values more than 15% apart.
oops: Stinkin appraisers!)


CubiCasa’s Digital GLA product is designed to reduce such variability by adhering to the ANSI Z765-2021 standard, which is required by Fannie Mae and Freddie Mac. Ha Ha Ha! CubiCasa for the win! See yah loser appraisers!

See too many big discrepancies with Cubi Casa to ever trust them

 

[Surf Cat]

See too many big discrepancies with Cubi Casa to ever trust them

Below the article Non-Seq posted above is another interesting article titled; Understanding Hybrid Appraisals. Keep in mind that it was written by the director of appraisal compliance for Reggora....the people pushing no sweat, 24 hour, no problems appraisals.

 

[alebrewer]

Looks like appraisers aren't special after all. Underwriters are going away also.

https://www.newrez.com/press-news/s...mevision/?utm_source=sprout&utm_medium=social

 

[Bobby Bucks]

No. But the point is the exposure draft is years behind what’s happening in the world outside of their echo chamber.

That reminds me of a thread many years ago where someone shared what happened after making a formal complaint about a specific AMC to their board. There was a long silence and one of them asked "What is an AMC?" The echo chambers of the notables in this industry doesn't know the day of the week most days.