If you are considering moving to a new city, spending a week or two in a hostel room downtown might make sense.
The hostel won’t offer five-star accommodation and won’t offer the best of the best comforts, but you will learn about the city’s realities when you stay there.
And during your tenure with the hostel, you will understand more about the city than you would if you stayed in a good hotel and tried to find a place to stay in the evenings and weekends.
The same logic applies when hiring a consultant, an advisor, or an expert.
It’s comfortable to hire a consultant whose company has a fancy website. It’s comfortable to hire a consultant who your brother-in-law has referred. Hiring the consultant who has “pleased” you in the initial discussion is comfortable.
But unless you have experienced working with them on a test/pilot project, it is all assumptions.
If you are hiring a consultant, advisor, or 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, have him come up with his perspective on the solution to the problem you have directly and/or indirectly described.
Observe what you feel. This is more or less what you will feel while working with him.
If it is too much uncomfortable, he might not be the consultant you want to have on your project.