Are you allowed to bring your dogs to meet this dog before hand? GSD's do play rough and require exercise, BUT this dog is a mixed breed and depending on what she's mixed with can change things...and change them alot. Some dogs require more mental then physical exercise and vice versa. Will you have a crate for her? Are you able to come home in the middle of the day to let her out? I seen a dog that looks like her yesterday, very pretty dog. She was a GSD/and ??...she was a rather calm dog, very happy. You also have the issue of 3 females, lots of people wouldn't even do 2 females, it all depends on their temperaments. Good Luck.
Misty- Samoyed Mix, Tannor- Golden Retriever CGC
Robyn- GSD CGC, TC, Midnite-GSD CGC,TC, Brennan-Golden Retriever CGC, Batman-Husky/Greyhound , Apollo-GSD