How to find rare model...sources, visual cues, websites, etc.

Check the vin
Vehicle Specification | Toyota Owners

 

Looking for a bargain on a very specific car while all cars are in short supply is... a more difficult challenge than usual. Now is a great time to be flexible about your needs.

If "bargain" is the most important part, stop looking on the internet. Yeah, it'll be harder for you to find a car, likely impossible to find the exact one you want- but it eliminates a lot of competing buyers and keeps the prices low.

I was also recently searching for a secondhand Prius with the ATP. cars.com and autotrader seemed to be able to identify the feature well enough, but there were only a handful of equipped cars actually available. Those are the ones people keep forever.

 

your focusing on bells and whistles, and that's fine, but i would focus on head gasket, oil burning, egr valve and brake actuator

 

Even if distance isn't a problem for you... If you can indicate a zip code or what region you live in it's way more likely you'll get some help. For example I'm in the Seattle, WA. and Portland, OR region and if someone is looking for a Prius in my area I'll start messaging ones I come across to help them find one. But if someone on PriusChat won't indicate where they live, myself and others will just keep scrolling.

 

Just to add detail to my earlier suggestion:

There are cork bulletin boards in the entryways of many grocery stores, laundromats, restaurants, and other small businesses.

I always see cars advertised on them, and they're nearly always put up by people who didn't list the car anywhere on the internet because they didn't know how or weren't comfortable with the idea. So they're taking a hit on the price because many fewer shoppers are seeing their ads- but for the bargain hunter this is how you get it done.

Obviously the selection represented by that form of advertising is quite poor and you'll spend a lot more time on the hunt, but it might be something you can train yourself to notice/check whenever you go out for groceries & laundry anyway.

And regarding the poor selection? It's not just old Priuseses, it's everything. I did some shopping looking for what I really wanted, saw how bad the markups & premiums were and promptly decided to kick the can down the road. I bought something else that will still serve the family just fine, and we'll trade up when the market settles down in a couple of years.

 

Its the only way to know especially before you travel any distance. Even if it were across town, checking the vin will tell the story. Sourcing it is using all the normal accesses. A Prius is not a cult or club car, it is an econo box with baggage, eg high complexity. Generally the gen3s are not a highly recommended used Prius from a reliability standpoint. I would buy a gen2 if I "had" to have a Prius on a budget. A conventional used Corolla, Civic or Camry would be my budget choice.