I leave a full hour to allow for overruns, answering the phone, emails, eat and drink, shower or bath, tidy and redress.
That's when incall, and seeing more than 1 client both of which are rare. Most of the time I'm outcall only 1 booking per day. Remainder of the time is doing the several other things I do in my life, showering, changing, answering enquiries, sleeping, taking confirmation, getting ready and travelling.