Installing bed edging
I have been doing bed maintenance since '97. With a flat shovel, I can do 20-30 feet a minute in normal soil if there aren't a lot of tree roots and the bed we are just cleaning up the edge. This just gets included in my mulch installation pricing. If you are cleaning up the edge, you'll want to mulch it anyway.
Creating or recreating an edge, when we have sod or weeds to haul away, we charge $0.50/ln ft. It's easy to create a good, clean edge 5-10 feet a minute if you know how to do it. Would come to
If we are putting in aluminum edging (never touch the plastic stuff), I charge $3.00/ linear foot. Around $1.75 is for labor/installation. The rest for the aluminum edging.
I never use a machine. Too likely to damage tree roots and pipes/wires without knowing it. Especially those dang cable lines.