OK, now we know where you want to go with this.
You're looking for a lighting maintenance contract/agreement.
My contracting business provided ltg maint for a national chain; we had a negotiated hourly rate for labor (with a base trip charge) and any materials we supplied were at 'cost plus'. The first hour was $xx, which included travel/trip costs with a hourly rate over the first hour. Materials was an 'average cost' plus 35% MU.
You have to negotiate/offer an hourly rate that goes with your locality, and remember you will have to 'stock' materials; bulbs, ballasts, etc.
Hope this helps, and perhaps someone else can jump in.