The Astros probably would want a premium young catcher and promising young pitcher for Lidge. Some teams would regard that as too high a price, considering the financial commitment that such a trade also would entail.
Two prospects for one reliever/veteran/closer with nasty stuff? Sounds about right. Why are GM's worried about money? Have they noticed how insane their bosses have been in the offseason spending money like drunken sailors on shore leave? Me no understand the financial commitment part so unless they're speaking of *one* particular organization (*cough, BRAVES, cough*) or most of the spending challenged (*cough, DEVIL RAYS, cough*) teams, if most teams want Lidge, they can make it happen.
I just don't think Houston is ready to make the deal, if they were so inclined to begin with, just yet.