How do you figure out R title price adj.

When looking to buy or sell a car with a rebuilt title, how do you make a price adjustment to reflect the reduced value?

It depends.  

On a newer car with a higher value the R-title reduces the overall desirability and therefore the price of the car.  

On a lower value car, such as one that is fully depreciated, like a car worth $4k in pre-accident condition, the R-title designation has little affect on the retail price of the car (though it should have some affect on the price.)

The real question is WHY was the car previously deemed salvage?  What is/was the extent of the damage and is there evidence to support the statements?  

Note that an insurance company deeming a car as "salvage" is a mathematical event.  If the car was worth $6k before the accident and now it just needs a bumper cover, a fender and a headlight the estimate may come back that it needs $3k worth of work.  Of course, that $3k is an estimate.  There could be cost over runs, hidden damage and additional expenses like rental car coverage.  So, at now with $3k+ damage the insurance company might decide to just pay the owner the $6k and close the deal.  This means no over runs for the insurance company.  Also, now the insurance company owns the former $6k car and the insurance company will auction that car off.  If the insurance company gets $2k for the hulk then that is $6k paid out and $2k back in or a net of $4k paid out for the insurance company.  For the insurance company that can often be an easier play than to do the $3k repairs with the risk of overages that could easily have them paying out $4k anyway.  

Now, add a zero for a newer car:
$60k car has $30k+ worth of damage.  
Do you really want to buy a car that needed $30k worth of repair????  That's a lot of repair.  That should hurt the desirability and therefore reduce the price...significantly.  

Things like flood usually means that the insurance company knows that the car will continue to have future electrical problems.  Those future problems would/could result in the customer returning there car many time to "continue" getting it fixed.  For this reason of avoiding never-ending problems, the insurance companies will usually "total" cars that have been deemed "flood".   As for desirability, you don't want to own a previously flooded car long term.  The problems may never end.  

At one time, I owned as many as 5 R-title vehicles at the same time.  But each were cars worth less than $6k in their pre-accident condition.  

What are some more specifics for what you are buying/selling?  

My CTS-V was totalled and thus received a salvage/rebuilt after the curtain airbags blew in a spin. The airbags and headliner (at least for slicktop) are both NLA from GM, so my insurer totalled it. Definitely hurt value of the car, which sucks, but goes to show that there are a number of ways to end up with a salvage/rebuilt title. 

In reply to John Welsh :

A guy with a UrS4 and a highly modified b5s4 avant is looking to trade (plus cash) for my s2 avant. Both his cars are R titled but minor damage (bottom of depreciation at time of event). Plus, honestly, I've always wondered. I know how it happens but seems more common now.  Likely due to the ridiculous costs of bodywork now.

Another item to consider is how long ago the title branding happened? Was it 8 years and 60k miles ago? Less concerning obviously than 3 months and 1000 miles ago.....

There is a significantly smaller pool of buyers for salvage title vehicles.  I know personally I would never buy one regardless of how good of a "deal" it was.  (other than the salvage title UGR TT purple lambo I passed on for $75k - doh) just too hard to sell on down the road.

I'm seeing these more and more lately, some branded, some not, but the carfax showing the accident, the majority of them occurring during Covid. I can usually tell there's something wrong because they're either priced like vans a few years older, or have what looks like a decent price, but exceptionally low mileage.

I would never buy one unless everything was well documented with pics of the repairs (I've seen this) and the pricing was appropriately low, which it never is.

Lots of very astute advice in here. 

I'd strongly urge you to pass on a salvage title vehicle. Repaired damage can have long term consequences that don't become obvious until you've owned the car for a while (tires that can't be properly aligned, water intrusion, poor structural repairs etc). 

It's also very rare that you're actually getting a good deal. Find examples of what a clean title one would sell for; market value is roughly half that.

As GSXturbo said, it's also much, much, much more difficult to get rid of a salvage car.

In my shopping I've generally seen newish cars with a rebuilt tile get a ~30-40% discount.  An R title might be more difficult to finance.  There's a much, much smaller buyer's pool.  Yea, you might save money when you buy it, but you'll also have to sell it at a discount.

I've considered buying a rebuilt newer car if the discount was heavy enough & I could find pictures of the damage.  FWIW, Plenty of older/cheaper cars can get totaled over fairy small damages where parts are expensive or difficult to source.  

Take insurance into account as well, some insurers won't touch a salvage title car.

My M5 has a salvage title. Other than coming to me with non-OE headlights (I fixed that), it's pretty darn hard to tell. It certainly hasn't been sawn in half and put back together. And that's how I could afford an M5.

50%.  My simple rule of thumb for anything previously totaled.

As someone mentioned above, these things are popping up for sale more frequently lately, but they are usually at 70-80% of regular retail which represents no bargain at all.  In my mind that's saving a little in light of likely ongoing headaches in the future.  I would rather pay more for a "clean" car.

I always happily pay a little too much for a car that is right to begin with because it invariably costs me too much to make them right after the fact.

Minus 40%