Great points made here. We went through something similar not too long ago. From that experience, I recommend you discuss at least the ball park of what they're

Great points made here. We went through something similar not too long ago. From that experience, I recommend you discuss at least the ball park of what they're willing to offer up front (and what you're willing to accept), before going through any further diligence. This way you can avoid going through an extremely distracting process and then only find out at the end that the offer isn't a compelling one.