Things always look better in the morning, Start with the simply things 1st before you sell,
1, Battery is fully charged
2, Turn IGN on does aall the lights come on
3, Kill stop in (Does it turn over??)
4, If not turning over or lights check fuses and side stand switch?
5, These are simply checks and any keen motorcyclest can do.
IF ALL THE ABOVE ARE OK TRY
1, Remove panels, find the fuel pump disconnect pipe from tank turn IGN (Key) and starter does fuel piss out? (Pump could be in tank so listen)
2, Remove tank, remove 1 X HT lead and plug, Put a spark in the lead (a new one) Does it spark?
3, if it sparks on all 4 HT leads, The problem is Fuel side
4, If it does not spark and you plugs are wet, ITs IGN side, Poss CDI,Kill switch,Loom,Short etc.
5, Change plugs and Fuel
Do these checks then you can get close to the issue.
Steve