well, I have given some advice before....I will give it to you with a caveat this time.
Taking a boat from Colombia to Panama can be managed with relative ease from Cartagena. Go to any hostel on or around Calle Media Luna in Getsemani and you'll find several ads up with info for the trip. My choice for decent advice would be Hotel Holiday (Or Holyday, depending on which sign you read) It's on Calle Media Luna, half a block east of Havana's. It will cost you slightly less than the flight......
Now, up until six months ago, I have never EVER heard of someone getting free passage for this route. Many have tried going down to the marina and begging passage to Panama....I lived above a hostal for a year, and never heard of a winner.
I gave this advice to an Australian six months ago. He refused to believe it, and later reported that with the expense of one bought Aguila and some Australian charm, he got free passage. So, if he is to be believed, this can be possible.
I don't buy it. I doubt that anyone would allow some freeloader on their sailboat as they sailed through the San Blas...But I feel honour bound to mention it.
To recap. Either pay about the same for a sailboat passage with some expat...or charm your way aboard for free at the marina in Boca Grande. I truly hope you score the free ride...but I am dubious.
GLOT
D