
Hello,
sorry to be blunt...but...of course you will be able to trust this lovely dog. He is only 7 months old and that age is quite horrible. Itīs like kids...some stages are cute, others are dreadful. Donīt give up. Your dog sounds like he is a naughty teenager trying for attention. Learn the Alpha techniques, talk with the family what are the rules for you all...stick to them, be patient...and in a coupla months youīll have a nice little friend that you can be proud of. He shouldnīt be learning to be mean and biting, but this is an age that we all think they are cute for a few months and they get away with murder, and then we have a big galloping dog on our hands who ( suprisingly) doesnīt show us any respect. Be tough AND kind, and give him lots of tasks. We started our dog running next to the bike at about 1 year old. It was so nice to go for a bike ride as a family, and our dog would be so happy and tierd at the end. Learning names for things and finding them around the house is also good....
Stick with it and soon, but not instantly, you will see some improvement

Annie