Second hand electric cars: how do you know what you’re getting?

I’d LOVE my next car to be a fully electric one, however apart from cost I never buy new because of the extreme depreciation of new cars – they simply aren’t worth it. I’ve gotten some good results from second hand cars (I traded my Hilux Diesel with over 550000kms still running fine).

So, I’d intend to buy a second hand electric car, however – how do you gauge “wear” of an electric car, in particular the batteries? I suspect it will be some time before I actually get one anyway, as I’ve yet to see a budget (i.e. non Tesla priced) mid to large car with acceptable Australian range (I travel over 150kms/day just to/from work), and a quick jaunt to Sydney would be over 400kms + driving around there.