The first three concerns I have not personally had to deal with on any large scale so hopefully someone else can come along to offer suggestions for those. My only advice is to remove anything that he guards and feed him in a separate room or his crate until you get it sorted out.
As for teaching quiet I have always had a lot of success putting nuisance behaviours on cue and rewarding them. When they start barking call it "Bark", encourage and reward it for awhile...then when he barks and you didn't ask he gets nothing. Throws them for a loop so in his puzzlement he will stop barking and when he does..name it "Quiet" and treat him. Once he has the two separately start chaining them together.