If you are thinking to move to a new city, it might make sense to spend a week or two at a hostel room in downtown.
The hostel won’t offer the five-star accommodation and won’t offer the best of the best comforts, but you will get to know about the realities of the city when you stay there.
And during your tenure with the hostel, you will understand more about the city than you would if you stay in a good hotel and try to find a place to stay in the evenings and during the weekends.
The same logic applies when you are on a lookout to hire a consultant or an advisor or an expert.
It’s comfortable to hire a consultant whose company has a fancy website. It’s comfortable to hire the consultant who has been referred by your brother in law. It’s comfortable to hire the consultant who has “pleased” you in the initial discussion.
But unless you have experienced working with them on a test/pilot project, it all assumptions.
If you are hiring a consultant, advisor or an expert, experience him/her for at least an hour (or preferably, a day) and work on some real task(s) together.
Sure, it is difficult to produce any tangible result within an hour or a day but observe the process: it doesn’t matter if you ask silly or intelligent questions, just have him come up with his own perspective to the solution of the problem you have directly and/or indirectly described.
Observe what you feel. This is more or less what you are going to feel while working with him.
If it is too much uncomfortable, he might not be the consultant you want to have on your project.