1. Check to make sure they have directly applicable knowledge / wisdom for you and experience in your industry. I've found that in the beginning stages of my startups finding a coach / mentor with specific experience in my sector gave me the fastest and greatest ROI.

2. Start with a short call (i.e. 30 minutes) and ask a very specific question. Be super focused and make sure the info you ask for (and get) is actionable. A small investment ($100 to $200) could result in a fantastic ROI. And remember that sometimes great advice / coaching SAVES you thousands.

3. Ask the coach if they offer an initial free consultation. But if you do so - be respectful of their time and if you figure out during the call that there's not a good fit - end the call asap.

4. Check reviews and get references. Do some online research and find out what you can about them. At the very least you should get a sense of what they are about.

5. Take action. Hey - you're an entrepreneur.. And taking risk is what we do. Absolutely do everything you can to mitigate that risk. But once you've completed your due diligence you just gotta go for it!

I have a couple of free calls left from my most recent offer. Should you wish to give me a try;
https://clarity.fm/davidberman/db3freecalls

In any case - best of luck!