Be sure to gather equivalent information from all candiates, so you will be able to evaluate them in terms of the same criteria.   This does not necessarily mean asking the same qustions of all candiates, but does require care in obtaining comparable information.

Keep on schedule but be flexible.

Set up a meeting with a realtor, if the candidate is interested.

Let the candidate be most of the talking, and leave time for questions

It is important to make the candidate comfortable, but avoid casual conversations that touches on inappropriate topics or inquires that are illegal in an interview.  The candidate could misinterpret such discussions, which typically occur during social settings.   All of the time spent with the candidate is considered part of the interview process, including functions and meals.