Ups, actually I did not…there aren’t many cars of the same type in CH, but same model, 6yrs old with 130k km costs around 13.5k CHF
Comparis says around 18500 CHF now, that would be around 7000/4.5 years = 1500/year
That brings the cost to around 0.22 CHF/km
No idea, however, how to compare that with swiss public transports (it depends, I think)…
To add a scenario, I drive a 6-year old diesel Honda CR-V (bought 1 year old with 7k kms) averaging 23k kms/year, and keep all costs strictly in software. Counting depreciation and all other costs, I average 0.47 SFr per km, so that Model 3 could be tempting…
I think your math is wrong here. Assuming 2 x 1500km @ 5L/100km = 150 L of fuel at 1.5 Sfr = 225 CHF. This is the marginal cost. May throw in a tiny fraction more for tire usage and oil service. You do not pay more in tax/parking/financing etc. based on this one trip.
Still makes zero sense with Wizzair flying for 22CHF/way BSL-WAW :-).
I think it’s tricky. If someone drives 30k kilometres per year, including trips to Poland, and his total cost per kilometre is 0.25 CHF, then 2400 km * 0.25 = 600 CHF. If you think that the fixed cost is a sunken cost, then yes, you just look at the variable cost before each trip. But I don’t think that’s correct.
Let’s see how they calculate for a cheap Polo:
Fixed cost: 4400 CHF per year
Variable cost in CHF per 1000 km:
Model 3:
So the Model 3 is as cheap to drive as a Polo, just has almost double fixed costs.
If it’s your car, just depreciation at around 30% per year. If you are buying new for a “buy and hold”, if it’s a brand with low maintenant, I’d say the major advantage comes after the depreciation is done … think all the taxis that buy a Prius new to burn 500k km on them (which would be amortisation for them)
But regardless, to have paper value of zero after 10years I’d say is completely normal for std cars…insurance will probably only give you residual value after 8 years in case of an accident…does get worse with high km but only to a point.
Not sure that this is a real consideration talking about a car at 52k chf though 
…
My main problem is that EVs are tech devices. They are outdated pretty fast.
Still, I think you need to decide how much of the value of the car you write off per year (fixed) and per km (variable). Then you get a formula:
car_value = depreciation_over_time + depreciation_over_distance
If the right side is larger than the left side, it does not make sense. So if you say that “a car depreciates 30% per year”, then you need to tell how much is a result of time and how much is a result of the car being used.
TCS calculates that a car will lose on average 10% of its initial value over 8.7 years (first more, later less). Moreover, they apply 2% depreciation per every 10’000 km driven. So if a car has driven 500’000 km in 10 years, TCS would calculate the total value loss at almost 200% of the purchase price, which makes no sense to me.
Let me try an analogy : I like to think of the “second 100%” as the main return on along term investment. The first 100% is your “investment unit price”…you get an initial boost in value (like tax deductions) then imagine for 8 years, the market stays flat or even goes down. You’ve already paid so you use your car (gas and maintenance are your TER that you want to keep low since its yearly costs). Then the second 100% is the moment the market breaks even again (100% depreciated) and slowly your initial investment (depending on the car) is doubled…the value it represents to you at that point is the “delayed dividend” a reliable car can pay you. Of course if you sell it too soon, someone else benefits from the “marginal (market) gains”…
At this point, I also reduce insurance to save more while I benefit from the car longer especially since it’s neither “worth” anything for insurance nor for fortune tax (double bonus). It contributes to its own replacement in that sense, even though its value to YOU is still almost consistant…this is the main benefit of “passive” cars like Toyota Prius’, but not at all the same thing as “replacement value”.
The difference I find is easier if we were talking taxis: in your example, the driver amortised off his first taxi (100%) then had time to save for his second taxi before he actually needs to buy it…thats the true value to him. He obviously couldn’t sell it at 250k km for a brand new taxi but to drive the same car 250k km more becomes basically the same thing to him…am I making sense?
In the end, “depreciation on average” doesn’t help you much since it only makes a different when/if you actually sell it. IMO, there is always a sweet spot for km driven vs age, but regardless a car that is 8 years old is usually not worth much unless we’re talking vintage cars like a Shelby Eleanor which are appreciating over 50years. I’m buy and hold on cars, but thats out of my league 
P.S. TCS recently screwed me on travel insurance, so I will never again officially agree to anything they say anyway 
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Well, it’s true that usually age and kilometres driven are correlated. But it HAS to be possible to distinguish between fixed and variable depreciation. So let’s consider two edge cases. You buy a car for 50’000 CHF and then:
How much do you reckon would the car be worth in both cases?
The reason I’m asking this is because I’m trying to figure out, in a fair rental agreement, how much of the cost should be time-based, and how much kilometre-based? I just know that the model where you pay 0 CHF per day, but 0.50 CHF per km discourages you from driving.
This would be bad for the engine/car, so it would depreciate it via a “confounding” variable. 
Hard to be black and white.
But you could look at some tables (rarely public though) where the manufacturers/dealers matrix the years vs. km to calculate depreciation.
Maybe you could reverse engineer a formula from the data - but that would again depend on manufacturer/brand/country, and would not be universal.
I was anticipating this comment so I explicitly wrote it… imagine that it literally teleported in time from 2016 good as new. There are some situations where the owner is just a retired sunday driver, takes the car to get groceries and to church. This car will make 10 km per day, less than 40’000 km in 10 years. But I expect it will not sell for a much better price than a heavily used business car with 300’000 km on the clock, right? Maybe the first car sells for 20% of original price, and the second for 10%.
I’m not looking for some exact science, just a fair estimate. For sure 100% depreciation does not come from driving. And for EVs its even more true, as they have a much simpler construction than an ICE car.
OK I see, I wasn’t reading as explicitly.
Let’s try with (off the top of my head, no concrete sources):
]Works approximately for my car when I got it at 3y old + 49k km.
But it shouldn’t work linearly, as the depreciation curve is more akin to something like O((2/3)^x).
So I am talking nonsense.
With your numbers, a 5yo car with 200’000 km would be depreciated in 150%.
I think the problem is, only the km depreciation is linear, the marginal time depreciation is decreasing.
The deal you are getting (0.50 CHF/km) is not fair, it’s obviously far too cheap. As you stated yourself, companies refund 0.65-0.70 CHF/km. I don’t think they just pay too much because they are nice to their employees.
Also if you look at mobility, the cheapest car you can get is 0.55/km and it’s not a Tesla. Also you pay 2.00.- per hour in addition. For the electric car you even pay 0.65/km and 2.50/h and it’s no Tesla either. I guess Mobility knows how to cheaply operate cars and also get special Deals for buying, service, maintenance, gas etc. Also the annual subscription costs 129/year.
Driving to Poland, alone, in a car is expensive, because it’s a bad idea (maybe you really need to go by car for some reason). A regular car has 5 seats, if you fill it, the cost per Person is only 1/5. Or you can use something like Flixbus or train or plane.
Also when people talk about the cost of a car, I never see the price tag for work/time. Someone has to bring it for inspection, maintenance, service, repairs, change of tires. The car has to be cleaned inside and outside. Are you doing any of this work for your friend?
Also when people talk about the cost of their car I always see the optimum case with just minor repairs. With my last car I had a Motorschaden after 3 years, it cost me 6000.- for the repair. I bought it for 12.5k and sold it for 9k after 3 years. So for depreciation and the big repair alone it was about 3.3k per year. I probably drove less than 10k per year. I guess the risk of big repairs is your friends risk, or are you covering/paying for anything like that? If you own 3 cars in your life and have bad luck with just one of them, the cost of driving is suddenly much higher.
I guess the CHF 0.50 just barely covers the variable cost and you don’t have the effort of bringing the car for inspection etc. So I think you are making a much better deal here than your friend. So I’d just be happy about the offered rate and not try to get an even lower rate.
You must be joking about Flixbus. Obviously I don’t look at the car hoping to get the cheapest way to get me to my destination. It’s a holiday road trip spanning one or two weeks. Visiting Munich, Berlin, Leipzig etc etc on the way, stopping wherever you please, transporting whatever you want with you.
I do it. There was so far only one checkup made after 60’000 km and it cost 600 CHF. Of course, once serious stuff breaks down, the costs can go in thousands, I know…
I do, whatever effort that is. I just drove it once to a Tesla salon nearby and picked it up in the afternoon. The same goes for tire change. I don’t know how else do you imagine it. He lives in a totally different place, you think he would come and take the car to do all these chores?
I disagree. I ran the calculation that TCS made and the variable cost is something like 0.21 CHF, or 0.18 if you forget the electricity. I know many people from Poland (frugal ones) who regularly drive their cars to Poland. They don’t go alone, as I also wouldn’t, but travel with their girlfriends/wives. 2400 km at 0.25 CHF/km gives a cost of 300 CHF per person. This can beat the price of airplane ticket for Easter/Christmas, which often reach 400 CHF. And it’s much more convenient if you don’t live close to Warsaw.
I had a look at autoscout24. There are plenty of Model 3 from 2019 (most not yet full 2 years old) with 30’000-50’000 km and purchase price of 60’000-65’000 CHF that are listed for 47’000-50’000 CHF. So 25% value loss in 2 years.
@Sandro one more argument: in Warsaw you can get a taxi for 0.40 CHF (1.60 PLN) per kilometre. And we know taxi drivers make many empty miles to pick up customers. And yet somehow he’s able to pay the variable cost and still earn some money. Of course, the cars that they drive are 5-10 years old and have driven between 500 and 1000 thousand km.
If you can offer a Model 3 for 0.50 CHF/km or even less, I think you should start a Mobility competitor. You’d probably be very rich very soon. Also I think the fixed cost should be shared between you and the owner, so why would you only look at the variable cost?
There’s also the calculator from ADAC (Die günstigsten Autos in allen Klassen: Autokosten-Check | ADAC) which also gives higher numbers than EUR 0.50/km. And I guess owning a car in Germany is cheaper than in Switzerland.
If you do long distances, you should probably rent a car for the duration. Like they normally offer at the airports. They are often very cheap (probably a lot of competition) and offer unlimited km. And I think sometimes you are allowed to cross borders.
If the owner is a good friends of yours, you could consider something like co-owning the car and share all costs according to the km driven. When the car is sold, you know the exact value for the depreciation and can correct the numbers you assumed before.
You missed the part where I mentioned a fixed daily rate, which would be paid apart from the kilometres driven. Just to be clear: I know my deal of 0.50 CHF per km is sweet, especially if I don’t drive too much. I just think if I was driving a lot more, then the marginal cost is much lower than 0.50 CHF/km.
OK, check this for example:
https://tesla4all.ch/vehicle.en.html?v=M3-SRPlus-White
Renting it for 4 weeks for 3000 CHF, 11’200 km included. That’s some 0.26 CHF per kilometre, and not a price from a friend, you can rent it too. For comparison, I would pay 5600 CHF for such a trip.
Ok, I guess I interpreted too much into it. To me it seemed like you tried to make a very good deal even better and thereby making it a bad deal for your friend. So, sorry for missinterpreting…
That’s interesting, I wonder how they can do it.
Yes that was stupid.
What about something like this?
f(x,y) = 1 - a^x - b*y
x: years
y: kilometers driven
0.5 < a < 1
a would probably be in the range of 0.8-0.9, depending on brand image / market.
(0.8 gives 50% depreciation at 3y only due to age, 0.85 after 4.25y, 0.9 after 6.5y)
b could be set to 0.0000025, to add another 2.5% down per 10000km.
But we could argue that this is also not strictly linear.
For your example the car of 5 years and 200000km, with setting a=0.8, would run it down to 17.2% of original purchase value.
After 8.5 years at same pace (40k/year, 340k km total), it would be run down to 0%.
From then on I would “write it off”, it wouldn’t of course produce negative value.
I think we need another variable/multiplier for brand image (e.g. multiply the end result by 0.8-1.2 for poor-great) or/and current market demand.
Or a separate model for the first 3-5 years, and a different one for older cars.
Enough math for today, fun exercise! 
After thinking about it and finding out it would be 400km per day (and also you hit the sweet spot with the 4 weeks discount), I guess most renters just drive a lot less.
Your trip of two weeks and 2400km would be 2k or CHF 0.83/km. Or, if you do it all in one week 1.2k or CHF 0.50/km (driving 343km/day on average).
So it’s possible, that if you rent it for 28 days and really drive 11’200 km, they lose money. And they might be able to do this, because most people drive a lot less. But I’m just speculating of course.