My anchor shops make my schedule by themselves each month from my accepting job offers that I get by email, but I still have to plug those offers into a calendar. I probably use one day total each month to adjust my schedule throughout the month. I try to avoid scheduling shops the last week of the month, so I will able to do the EOM rush shops. If I am going on a route out-of-town, I may have to take some time for the logistics of that trip. How much time depends on factors like how many shops the trip includes, where the shops are located, the hours they can be shopped, and whether I've shopped them before.
I usually don't have time to look through every job board, even though there are not than many for me to look at. Emails are so much faster to sort through than job boards are. That's especially true with companies who just cannot design a user-friendly website that works.