It truly is essential you check the counselor's credentials. Anyone can pay to get a degree printed with their name on it, but that doesn't make them certified. You want the names of the universities they attended and then research them. Plus, it gives you an idea showing how long they have been in practice.
Next, you want to check their location. If they are not convenient to where you live, then this will automatically give you an excuse to not keep an appointment, particularly if you are having a particularly bad day with your partner. Couples can also get premarital counseling at http://www.parmlaniado.com/.
Even after you have your doctor's recommendation and have validated the counselor is effectively qualified, you still have to get an appointment. If they are reserved up for a month, this isn't going to do you worth it, particularly if the situation is a significant one. A lot can happen in a month. It could even be enough to cause irreparable problems for your relationship.
When you go to your first appointment, it's greater than a meet-and-greet: it's time to size them upwards. Maybe you can talk with them on the phone before making an scheduled appointment with them. You need to be comfortable with your counselor or perhaps you won't be completely honest and open with them.
If you don't feel completely at ease with them and the approach, start your search over.