What's the best used, small, automatic car?

I'm looking to buy a used, automatic, small car for my 22-year-old son. It will be his first car and our budget is £3000 - £4000. Ideally it will be a low insurance group, but I mostly want you to recommend...

Who makes the most reliable automatics?

Which car brand offers the most reliable automatic gearboxes?

Which cars have a torque converter automatic transmission?

Which automatic new cars in the UK still have torque converter gearboxes as many manufacturers seem to be switching to cvt or twin clutch?.

I'm moving from a normal automatic to a CVT gearbox - are they very different to drive?

After nearly eight years of living with the 2015 Honda CRV automatic we are getting the new Jazz in March. I haven't driven a CVT model before, and wonder whether you have any tips for someone who is making...