I agree with what the others have said. He's not reliable enough to be left out right now. He's still very young and Boxers are high energy dogs! Crate him for a couple more months and try it again. Make sure you're not leaving anything out the could be enticing to him. How much exercise does he get? Try leaving him out only if he's had a lot of exercise right before you leave. Other times put him in his crate. If he is allowed to destroy things he get into a habit and will keep doing so.
Our dog took until over 3 years old to be okay out of her crate. Then at Christmas last year she started going backwards and destroying things again so it's back in her room. We'll try again once she's "forgotten" to chew things up. Our other dog is 3 now and still can't be left out of his crate. We felt bad too because he also sleeps in there at night, so we decided to start leaving his crate door open at night. Guess what - he cried and howled and scratched at the door to room, then started shredding things. I got up and put him back in his crate (he was happy to go in) and he went right to sleep.
Keep in mind that some dogs will never be okay being left loose at home alone.
Our dog took until over 3 years old to be okay out of her crate. Then at Christmas last year she started going backwards and destroying things again so it's back in her room. We'll try again once she's "forgotten" to chew things up. Our other dog is 3 now and still can't be left out of his crate. We felt bad too because he also sleeps in there at night, so we decided to start leaving his crate door open at night. Guess what - he cried and howled and scratched at the door to room, then started shredding things. I got up and put him back in his crate (he was happy to go in) and he went right to sleep.
Keep in mind that some dogs will never be okay being left loose at home alone.
