the Trick for the Rays has been success developing guys from their drafts and INT signings like Austin Meadows that performed well enought to trade for some thing younger and cheaper to keep the wheel turning. You can say they've done exactly the opposite of the Tigers in recent years. Instead of letting Suarez, Paredes, Adames, develop in Detroit, get close to expensive and then trade them to get younger, Detroit traded those guys when their value was low to get *older*. Not the way to run a low cost team, though we know Dombrowski wasn't necessarily interested in running a low cost team!
But to bring this back to Perez, he looks to me exactly like the kind of guy a Tampa Bay would hold onto until he has established himself, his value was higher and his cost was about to go up. And that all comes down to being right about both your own players and the players you scout to pursue.