I'm in a similar position to the OP. Current car is getting on a bit and am starting to think about an upgrade. Being a geek, I am keen on something electric, but from what I've been able to find out, I am not sure that the current costs totally stack up. There's a lot of assumptions in this, so would be very keen to hear if I've done something wrong (since that would be the justification to Mrs MDF to go electric).

Our commute varies from day-to-day, but the max round trip for any day is about 35km and over the working week is about 100km all up. So well within the range of a Nissan Leaf. Comparing that against a similar hatchback:

Using Energy Wise website figures (which might be a bit out of date), it takes 15 kWh for a Nissan Leaf to drive 100 km. At 15 cents per kWh that's $2.25 a week in electricity (that probably needs an uplift for charging inefficiencies but I'll use that figure) = $120 per year. Energy Wise suggests a modern-ish Corolla will do the same distance in 8.5L. Our older Ford Focus would use 10.5. At $2.20 per litre that's $23 a week in petrol = $1200 per year.

Registration is $52 per year for a passenger car (excluding ACC levies, but I believe they have to be paid for BEVs too), vs 0 for the Leaf.

I pay $200-$300 a year to service our current car. Some years is higher (brake pads and discs), some lower. I would guess a more modern car will need less servicing. Most sites seem to claim that servicing costs for BEVs are near zero due to the mechanical simplicity, but I assume there has to be some cost for power steering fluid and brake pads, even if is is less. But again, assume zero.

It's hard to find figures, but the batteries in a BEV will deplete over time. The service doesn't seem available in NZ, but it's possible to swap batteries in the states for about NZD 7,000. I'm guessing that will come down by the time I need to do this, so say NZD5,000 maybe? Taking that over ten years is the equivalent of $500 per annum.

Tyres I am assuming will approximately be the same for both so nets out to zero.

So my maths makes it about $1550 ish per year for a petrol hatch (1200 petrol, 300 servicing, 50 registration) vs $620 ish for a BEV (120 electricity, 500 battery wear). For both, ACC and tyres need to be added to that.

Being generous, that makes the BEV $1000 per year cheaper to run (though I actually suspect a bit less than that).

Over maybe ten years, that stacks up to a $10,000 difference in purchase price (I'm sure there is some kind of future present value of money I should be taking into account too). Obviously the longer commute would favour the BEV more and more.

Just from google searches and dealer advertised prices, you can get a recent mid-spec 24KW model Nissan Leaf with a good battery state of health (85%+) for around the 25K mark. According to the specs, that only buys you twin airbags though. The ANCAP rating gives the Leaf 5 stars, but that is based on surround airbags. You need to go up to a G-spec level at more like 30K to get surrounds airbags.

For that kind of money, you can get a brand new Corolla with 7 airbags as standard. Even for the 18-20K-ish mark, all recent Corollas seem to have at least front and side airbags (though I've found that hard to confirm).

Is there something I've missed in this?