Earlier this week, Caddy told Gold Coast he wanted to be traded to a club in his home state of Victoria.
But football manager Marcus Ashcroft said the Suns would demand nothing less than a favourable trade for the rugged midfielder.
Caddy also requested a trade last year, but when Essendon offered pick 19 in return, it was rejected.
"Our philosophy is we have to do what's best for the footy club. The trade will be in the best interests of our list and our team going forward," Ashcroft said.
"He's had another year of footy, he's one more year experienced, played every game. How do you work out what's reasonable?"
St Kilda and Geelong are rumoured to be leading the chase for Caddy, who was one of just three Suns to play every match in 2012 and is tipped to quickly become a star of the competition.
The Saints, who finished ninth, could offer the Suns their first-round draft pick or a potential compensation pick if free agent Brendon Goddard decided to leave.
Reports suggest the Cats, who will have salary cap space if Matthew Scarlett retires as is expected, also have strong interest in the 19-year-old.
If a deal cannot be struck, Caddy would have to take his chances in the draft, which would mean he would not necessarily go to the club of his choice.
That would leave Melbourne and Western Bulldogs, the two Victorian clubs with the highest picks in the draft, in prime position to snare him.
Caddy, taken with pick seven in the 2010 draft, said it had been a 50/50 decision to leave and thanked Gold Coast for their understanding.
"I do though believe the move back to Melbourne is the right thing for me," Caddy said in a statement released by the Suns.Do you want to walk out in front of 90,000 people at a packed MCG and toss the coin at the 2012 AFL Grand Final?
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