The other issue about phased payments is that it makes Motability a lender, governed by all sorts of complex financial legislation.
I’d love to see second hand cars on the scheme, especially if it means models way above what is presently offered, but I can’t see that happening either. The simple reason being that Motability gets a block VAT exemption which means they are paying second hand prices anyway! Besides, VAT exemption only applies to brand new cars.