At this time our yard is not fenced. Talos is 11 weeks old and we are getting ready to fence our yard to give him more freedom to run and play. We know that boxers are pretty good jumpers and want to do our best to protect him. We feel like a 6ft high chain link fence will look very institutional. Is a 4ft fence good enough? Obviously we need to train him but we don't want to risk anything until he's learned. How high are your fences? Have you had any issues?