It's not a good idea, @Judy689 , which is why Airbnb makes that very, very hard. You have noticed that you cannot send contact information before a booking, that it is masked.
Walk-throughs are not part of the deal, and I love being able to use the rules to back me up in not granting them.
You can find it in the Help Centre here: https://www.airbnb.ca/help/article/47/what-should-i-do-if-a-guest-wants-to-see-my-place-before-booki...