It is permissible to use funds of such a player still on your roster. During the auction, for a player to qualify for a position, he must have played that position at least 15 times last year. During the season, a player may become eligible for other positions if he plays at least 5 times at the position. During the auction a player may be agreed to be eligible for a position that he is apparently playing for the current season but is otherwise ineligible. Some players may be eligible for several positions, others for only one.
Any player is eligible to be brought up for bidding.
Injured players and even minor league or AL players may be bid upon if the owner feels it to their best interest to acquire that player for his bid. Bidding proceeds in auction style with the highest bid acquiring that player. Final bid becomes that player's salary. Bid amount is deducted from that owner's limit. And the owner must have a roster position available for which that player is eligible based on his position qualifications.