For a booking Request, you aren't charged until the host clicks on "Accept". They might do that immediately when they receive your request, or it may take them some time to do that, or they might message you first to make sure you have read through the listing info, have entered the correct number of guests, etc. before accepting.
If you just want to ask the host some questions before committing to a booking, you should send an Inquiry, not a Request. To send an Inquiry, click on "Contact Host" at the bottom of their listing description. An Inquiry doesn't commit you in any way and even if the host pre-approves it, you won't be charged until you take a further step. But the place could get booked by someone else between you sending an Inquiry and the host responding., so there is no guarantee that the dates you are inquiring about will still be available if ad by the time you decide to book.
@Elizabeth2090
