hehe Seven months does seem to be an age where many dogs embark upon their war of destruction, and it can last several months, or for life if not treated.
Aside from moving everything out of the house, I really don't see that there is much choice but to confine the dog in some way. A crate would be ideal for this. They sound and look much worse than they are, really. I know many dogs, mine included, that like them so much they put themselves into them.
The alternative is that you come home, see something else chewed up, and lose your temper with the dog, or become very disappointed. Either one won't be pleasant for the dog, and certainly more unpleasant than being confined in a crate, or if possible, perhaps a single spare room.
Yes, a crate is a cage, for want of a better word. Like these.
They are not for penalty or punishment however. On the contrary. As stated before, my dog loves her crate/cage and often goes in on her own accord to get some peace. I use it when I want to be sure that I can leave her and she won't get into mischief or danger, as dogs of that age can so often do. I know they can look a little stark, but you can put soft bedding into them, as well as dog's favourite toys.
If your dog is used to sleeping in a room alone at night, then I see no reason not to use that same room throughout the day while you are out, providing that the dog has plenty of toys to chew, water to drink, and plenty of exercise and attention when you are at home.
hi Ivan- Assuming your dog is NOT suffering from separation anxiety, there are several things that you can do at the same time to solve this problem:
1. Like collieman and Jean said, confine your dog when you are not home. You can use a crate, I prefer to use babygates to section off a small part of the house, like the kitchen for example, so he has a bit more room to play with his toys by himself if he wants to. You can use the room he sleeps in, but it should be "puppy-proofed" - no things he can chew on that will be dangerous, like electrical cords, furniture etc. By confining your dog, you are preventing him from engaging in the unwanted behavior in your absence. (The more he practices the unwanted behavior, the more of a habit it will become.)
2. Leave your dog with safe things that he IS allowed to chew on. Hard chew toys, kongs for example, so he has some outlet to work his jaws and brain. No things that have small pieces that he can tear off and swallow (and possibly choke on), like squeaky toys.
3. One reason he is being destructive could be due to boredom or excess energy, and 7 months is where they are entering adolescence and will have very high energy levels. Before you leave your dog home alone, give him a good exercise, training, and play session to tire him out. Then when you are gone he will be more likely to sleep rather than go looking for things to do, and it will make confinement much more pleasant for him if he is already happy to spend the day sleeping. This is very important.
4. Other ways to work off his energy: put his meals in food-dispensing puzzle toys like kongs, buster cubes and similar toys, you can get these at petstores. And give these to him when you leave the house, like in his crate or in his puppy-proofed room, so it occupies him with something useful and fun when he is alone. And it helps work his brain so when he's done with the food-puzzle toy he will be less likely to be bursting with restlessness.
5. If you really can't put things out of his reach, you could try spraying bitter apple on them. You can buy bitter apple sprays at the petstores, it doesn't stain things, and it is non-toxic but it smells and tastes disgusting to most dogs so he will be less likely to want to put his mouth on them.
However, IF your dog is being destructive due to separation anxiety (meaning that your absence makes him panic and he "loses his mind" with anxiety and that's why he's destroying things because he can't control himself in his panic), then that's a totally different and more serious problem and requires different solutions. Symptoms of separation anxiety are if the destruction is centered around the doors (the dog is trying to claw his way out to get to you), or if the dog hurts himself in the process of destroying things and still keeps going, or if he also loses control of his bladder or bowels (but he is otherwise housetrained when you're at home), or if there is a lot of howling and crying and whining when you leave and continuing on when you're gone (your neighbors can tell you this, or if you just wait outside the door and listen), or if your dog becomes extremely anxious when you are about to leave. if any of these apply to your dog then a different approach to treating the destructive behavior is needed.
My dog Sandy used to be shred paper or anything else she could find when she was left home alone.
I didn't want to use the crate, as my other dogs were not destructive and were allowed free run and I didn't want Sandy in her crate while the others were running around playing.
Instead I decided to take her out for a jog before I leave, or take her to the park for an hour, to tire her out. I found this very helpful and Sandy stopped chewing or shredding things she isn't supposed to.
Also, I stuffed her kong with things like liverwurst or peanut butter and then put it in the freezer over night - it occupies her for hours!
Seeing as your dog is young and full of energy, it will probably be a good idea to exercise him before you put him in his crate for long periods of time.
if you're at home, watch him so you can re-direct him away from the leather items to his own chew toys right when he starts going for it (not when he's already been happily chewing the leather for ten minutes!)
if you're not at home, put the leather items out of his reach so he can't ingrain the habit of chewing them when no one's around to stop him.
Or, you can spray bitter apple on the leather items so he doesn't like the smell and taste. You may have to do this consistently every day for weeks for him to get into the habit of staying away from the leather items altogether, it works best if combined with the above two techniques.