the important thing is to speak to motability and as philjb says enquire about grants to assist with the ap.
also check the real world fuel economy of any you shortlist there are many websites you can do this on the manufacturers tell porkies and the tests they run are not the same as in the real world.
or even ask on here i am sure someone will have one of the vehicles you like and i am sure they will assist with any questions you may have.
good luck