Depends on the job. I've scheduled some so that I can do them in the sumer slow down, "I'll come down to $XXX if I can scheduale at my convieniance." Or say that it is a deadwooding of a green ash, "I'd like to do it after the leaves are out so that I can see what is what better. How does the first week of June sound?"
Or if it is a smaller job, maybe a few hours tops, "can I show up at any time to do the work? I'll just slip it in to the rout when I'm in the area."
Is it an easy weekend job that and they want it doen right away? "I'm pretty booked right now, but we could do it on Sunday morning, but I pay they Guys double time for that." Or how ever you can do it without feeling your gouging. "We can run by on our way home some day in the next two weeks for $XXX"
Scheduling and routing will make it ebvery time. Getting those little jobs that round off the day, knocking the edge off of a long drive back. Or a short one for that matter.
The real trick is to not let any leads slip away.