we started doing lighting for a few of our customers a couple ayears ago, start week before thanksgiving/ take down usually 2nd week in january.
we have a bucket truck so that really helps when your doing big trees. but mojority of work can be done with ladders and pruning poles with saw head removed.
i buy all materials from a local lighting dist. by the pallet we use 100 ct strings ( easier to wrap around trees)
spools whenever we are doing roofs or straight shots.
we also do greenery - christmas trees and wreaths
startup is pretty cheap - ladder is really all you need for the smaller truck rent a tow behind man lift for the bigger jobs.
make sure you have an electrician go over loads if your doing big jobs . sometimes we have a local company run a line from the main to power all the lights and then have them look over everything and give us the go ahead. good idea incase anything happens ( fire...) we usually stay away from c-9 lights for that reason they get so hot and draw so much power.
follow manufacturers suggestion for # light string in row - another cya thing incase something happens nobody can get you for negligence. also makes lights brighter when string has less draw on it.