I will preface my post by saying that I do not mean any ill-will towards you and am not judging you in any way. However, you have some major misconceptions regarding the breed, and I hope you will spend some time on this forum to learn more about the breed before purchasing a German Shepherd.
A well bred German Shepherd from a reputable breeder will generally run 1500-2000$ for a working line and will be 1500-2500$ for a showline. This is because health testing, buying good breeding stock, training, showing, traveling for shows/trials, feeding high quality food, caring properly for dogs, vetting, proper living conditions cost a LOT of money. Most breeders that do it right break even (if that). I would be highly suspicious of anyone selling a GSD for under 1000$ because there are almost always shortcuts being taken if a GSD is being sold for as little as 375$. I would be very surprised if the breeding dogs had any health, temperament, or working testing done. If you cannot afford a puppy or dog from a reputable breeder, look into local GSD rescues and adopt a dog for a minimal adoption fee. This way, you do not support shady and unscrupulous breeders.
If your dog has to stay outside, she should stay in a pen sized about 10ft by 6ft or larger. Provide the dog with a size appropriate dog house with straw or some form of bedding inside. Igloo dog houses are very good and provide good insulation during cold/rainy/snowy weather. You can cover the pen with a tarp or kennel cover to provide more shelter. German Shepherds do not need jackets - they are double coated dogs and need adequate shelter rather than a coat. Bringing her inside at night is also a good idea.
Have you bought this dog already or are you planning on getting another dog? Your post isn't very clear in this aspect. If you have not bought the dog yet, do not buy this dog, and wait until you are properly settled into your new home. Moving is very stressful - wait until things are calm before adding a family member.