But @mvcanada the vehicle make may change over time. There may even be multiple makes using the same charger. How do I plan for that?

I'd plan by getting the voltage you need to the garage. That's as far as you have to plan. The charging cable on the charger we have is plenty long that it could reach the front of the car or around the other side if it had to. I'm fairly certain as well that you can likely get "extension" charging cords with any home install models. I think you're going to have to make a decision on your vehicle and work with it. Technology around charging is changing quickly. By the time you are ready to replace your vehicle, you may need a different charging station anyway.

Buy your car and enjoy it.

Don’t overthink this issue and I agree get the car first.

I am in the planning stage for adding wiring for a future electric car charger for an unknown car. The electrician suggested a location at the middle of the back wall of the garage since it is closest to the breaker box. If I have a car with charger at the rear, the car can be backed in. Putting it on a side wall is a farther distance and she said the shorter the wire is run, the less expensive for me. Back middle allows it to be used for a car on the left or right side of the garage as well.

Really the cost of running a bit more wire from the breaker box is negligible and that should have nothing to do with where to put the charger. I would not want to back into my garage all the time in order to plug in the car,

Google this and give it to your electrian

How To Wire A New Garage For Electric-Car Charging: What ...

https://www.greencarreports.com › News › Electric Cars

Feb 26, 2016 - Many owners will want to retrofit a charging station into an existing garage, but to lay out the principles, we're starting with what it takes to install ...

I was going to say the same thing as Patricia Colwell Consulting. Consider the specs of the car you are looking at and how often you will be charging based on the battery range. Will you be charging 2-3 times per week? If so, I would not be trying to back my car into the garage that often. In fact, I wouldn't even want to do it once a week.

If you are unsure of which vehicle you are buying have the electrician run the wiring to the garage and leave enough length of wire that it can be finalized once you've purchased the vehicle. You want your nice new car to be convenient. You'll love driving by the gas station and not pulling in, but you won't want to have a hassle each time you want to plug in your car. Do it right and spend the money with the electrician to put the charger in the proper location, not where it is easiest or cheapest. In the long run, your gas savings will more than cover any outlay to run the wire a few extra feet.

I recently had a Tesla Wall Connector (24' cable) installed in my single-car garage. The electrician ran conduit up the outside wall from the main service panel into the garage, then along the inside wall of garage to a spot about 3' from the garage door. I can't imagine any car, with any port location that the cable wouldn't reach.

Had I not known in advance that I would be getting a Tesla car, I probably would have installed a NEMA 14-50 outlet to use with charging cable designed for EV of choice. If I had a two-car garage, I might place the charger/outlet near the center of the back wall to maximize my parking/charging options.

Disclaimer: these comments come from a happy EV owner with zero professional/technical expertise. I did a lot of reading and trust my electrician.

To minimize electrical voltage losses and heating in the charger/cable

The extra few feet to have it in the position that is most convenient will not increase the voltage loss any significant amount. So don't worry about that.

I am proposing that sub-panel be installed

There's no need for a sub panel if it's only supplying the car charger. Don't waste money on installing one. Just run the wire to a junction box and then hook up the charger whenever you get it.

What do you consider a "few extra feet" ? In my case, it would be 10 -15 feet from panel to the back wall, vs an additional 30 plus feet to go up the garage wall, along the ceiling and back down to be near the garage doors. I will clarify the costs and how long the charging cord can extend from the wall. ** Per the Tesla website, the charging cord comes in a 8.5 or 24 foot length** so no need to back in if plug in spot is at the back of the car.

30 feet is nothing. Don't worry about it. If it was a few hundred extra feet, then you might want to start doing some calculations to see if it would be worth it to upsize the wire.

There is already a safety factor built into the sizing of wires required by code to account for voltage loss over typical distances.

Obviously the closer to the panel, the less cable you'll need to purchase and therefore the initial installation will be slightly cheaper. But the ongoing cost will not be affected.

By the way, the length of the charging cord from the unit to your car MAY be a factor that you'd want to consider. Those types of cords are not under the same code standards as your house and are often optimized for wire thickness (so that they are easier to move around) as opposed to electrical efficiency.

Ever notice how the cord on your vacuum cleaner is warm after you've been using it for a while? That's the voltage loss resulting in heat. But you wouldn't want a big chunky cord to lug around while you are moving throughout your house.

Again, it may not be a significant loss, but I think that length would be something that you might want to consider. It probably isn't significant enough to inconvenience yourself, but don't get the longer cable if you aren't going to need it.

A plugged in car is a happy car. Ideally you want your car plugged in any time it's in your garage for longest battery life and to insure that you're always ready for wherever you want to go. SO, you want your charge cable convenient to the port on your car so that it's as easy as possible to plug in. Ideally you don't want to have to unhang extra cable each time you plug in and then coil and hang it back up so a setup that allows you to quickly grab the connector and plug it in and then unplug and put it in its cradle with one motion is best.

For our Tesla's the charger and cable hanger are located on the drivers side of each garage door. Takes about 3 seconds to plug or unplug.

Leaf was a bit more of a pain because I had to pull the cable across to the middle of the front of the car. Putting the extra cable loop on a weighted steel cable would have been a good idea but I never got it done.

SO, you'll want to configure your charger for each car. The charger and cable head do not need to be in the same place. So you could put your charger in the middle of the wall next to your car and then put the cable and handle hanger nearest which ever end of the car the port is on.

There are photos with this idea already implemented, it sounds interesting.