I know a lot of it is dependant on location, but $1,200 to have a 240 volt outlet installed seems excessive. The vast majority of posts on it that I've seen put it in the neighborhood of a few hundred dollars. Yes, some people may need service upgrades or additonal panels or some other additional service, but for those people I would hope that they would take that into account.
Can you provide a source for that 10-20% recomendation? According to the 2014 census the median household income was a bit over $53,000 dollars, using the 10-20% figure the median car purchased would be 5,000 - $10,000. Forget your 25% figure, your well into the 91st percentile of income to even be able to afford a $35,000 car. Yes, people often spend more on things than they should, but there's no way half the country is spending that much more on a car than what your 10-20% says they can afford.
Perhaps the 10-20% is for payments? That sounds much better, and then it makes the car much more affordable to everyone.
How?