They have somewhere between $8-10 million in space depending on what the final salary cap is this season(rumors are it might be around $122 million). Keep in mind that at around $4-6 million of that space will have to be put aside to sign their draft picks, so they probably only have $4-6 million to spend at this moment which is nothing with all their holes to fill. Miami is also going to be losing some starters but at least the Dolphins have around $44 million in cap space and a lot of high draft picks.