Main Relay.

I would have no doubt...those symptoms sound all too familiar. Will it turn over...and over...and over...about 10 times you'll try this before it starts.

Does it have a tendancy to do it more often on 'short' trips?

My suggestion...Main Relay...which is just down underneath the dash behind the coin box on the left hand side of the dash...right near the hood release.

If that's not it...I'm as stumped as you are.

Jason