What concerns me more than ANYTHING here, is that her dogs are "left outside"
Boxers are under NO CIRCUMSTANCES "outside dogs". They should always be indoors, unless you are letting them out to potty or exercise (supervised). Their short noses, combined with short coats do not allow them to tolerate extreme heat or cold.
Several people have very elaborate, sheltered dog runs, which can be an exception, but please do not leave your Boxer outside in the backyard unattended.
That being said, when you put your dog inside, you will often notice that they get into things that they shouldn't, or potty where they shouldn't, or chew things up out of boredom or seperation anxiety. This is where a crate comes in handy. It's for their safety, and is a very useful training tool.
Please bring your Boxer indoors, and buy a crate