Basic Fiat Panda (latest one) is often recommended in the motoring press, smaller engined ones are Group 1 insurance, so you might end up paying less for the insurance than the cost of the car.

Take four adults, although I found shoulder room a bit tight, but I'm a bit wider than average.

Smallest Micra insurance group 2, choice might depend on if learner is male or female, Micra's look so girly, the only males who would drive one are trainee hairdressers.
Suzuki Swift very highly rated, even Clarkson said it was very good, looked at one the other day, and was very impressed, but insurance a bit higher.
