Please don't give up ! For the neutering , it will not do miracles but do calm (a bit !) some dogs , but not all of them. For the pooping inside , I would suggest to take him to see your vet, just to make sure it's not an health problem.
For the behavior issues , this dog sounds like he needs exercise , lots of it. How long do you walk him , how many times a day , how long do you play with him outside ..... the more you do , the more he will be tired and will listen to you and will not feel the need to be
