It sounds like your dogs need to be neutered, to help curb the marking-it WILL help. Only intact animals have the obsession to mark things. Do it sooner than later as they have already started and it is much easier to prevent than fix. Neutering is still going to help, it just takes about 3 months for the hormones to leave their bodies. What about maybe some crates? That should help you control them when you can't watch them. It helps save the furniture and the house! good luck!

Do your dogs have toys of their own?? I give my dogs toys to play with and the have never bothered my furniture or things. My sister puts her puppies in a spare room which has no furniture ( just blankets to sleep on and toys and water bowls)until they get older. She brings them out when she is home to watch them but they have seperation anxiety when she leaves them alone and would tear things up. She says the smaller space helps them feel more secure when shes gone. Perhaps you could try this or if the dogs are small enough a large crate for when your not a home. Good luck!