I agree with everyone else if they have never booked before you need to speak to them on the phone to feel out their personality and whether you think you will click or not. It's not foolproof but it is worth it so make them call you to confirm.
Plus just wanted to add that if it makes you uncomfortable in any way or puts you off accepting the booking then it is a red flag for you, everyone has their own personal red flags so if your spider sense is tingling then always cancel. Better safe than sorry.