I've got some hotel bookings for Barcelona ( and also for Belgium)later this year. with most of them to get a better deal, I've taken a saver rate which means I've paid some money or all of it up front.
My advice would be to leave making your booking till your plans are set in stone, but then of course, if its peak weeks, you may not find decent accommodation available.
FWIW in our business,(in common with other similar small establishments) we charge a non refundable deposit.
Yes, you can charge a card without actually having it front of you. You just need, Long number, expiry date and cvc code.
If you are going to send details by email, then split the card deatils over 2 emails