Driver Idle
  ping received -> Evaluating Opportunity

Evaluating Opportunity
  accept -> On The Way To Merchant
  decline -> Driver Idle

On The Way To Merchant
  arrived -> Taking Photo

Taking Photo
  # merchant notified that photo was taken, recipient notified that driver is on their way
  photo taken -> Out For Delivery

Out For Delivery
  deliver -> Inspect Package?

Inspect Package?
  # notify merchant of good delivery + trip time (or other details as needed)
  good? -> Driver Idle
  # notify merchant of bad delivery
  bad? -> Returning Package

Returning Package
  # notify merchant of return arrival
  arrived -> Driver Idle