You have one or more of
1) bad battery
2) bad power connections
3) bad fuse holder
4) bad fuse
5) bad key switch
Could it be a failing solenoid? If you are brave, :confused2: place a well insulated screw driver between the 2 screws on the solenoid and see if it starts. If it starts, could be the solenoid. If you have a safety switch on the seat, someone will have to sit on it, while doing this.
You are right, I missed that he didn't have any power the second time!