If it's in-person, be mindful of being watched/listened to before and after the interview. Like, if you say you got a lift but got off at the bus-stop outside the place. The nice receptionist is likely taking notes too. Anyone accompanying needs to be aware of the need to be careful what they say. You get well-meaning relatives chatting about what their morning's been like (including the client's) to other people in the waiting room and it's a big no cause they'll twist that. Any little thing they will use against you. You probably know this
hitmouse but worth putting here I think.
Some great links on the previous page, nice one. And yes, don't rush to give answers.
In a society that encourages people to play down disability/health issues and not make a fuss, it can be hard to lay it on with a trowel how bad it can be but it's necessary here.