Welcome:
Breeding is not for anyone faint of heart or weak in the pocket.
There are many things to consider when it comes to costs.
First is getting a really great bitch. Will you be getting an adult or a puppy? One must remember that puppies are a crap shoot. You may put out $800 and get a great bitch with breeding privledges. You may put out $1200, and get a puppy who has elbow dysplasia or any number of genetic faults. You could put out $2000 and still end up with a bitch whose physical health, temperament, or conformation just does not add up to a decent breeding prospect. So consider carefully about getting an adult female whose hips and elbows are checked, and is physically what you are looking for.
Also now is when you need to decide what you are actually wanting to breed for. I do not mean money or to have cute little puppies. I mean German showlines, Working lines, American Lines, a mix of these, temperament, showing in conformation, SAR, Schutzhund, obedience and Rally, working police dogs, herding, tracking, etc. If you say that you want to breed companion animals, then you will be roasted on this forum (I kind of did that). I have a theory that a great percentage of dogs will be companion animals and nothing else, and of the percentage that are not, it is hoped that they are companion animals a great percentage of the time. Which means (to me) that these dogs need to be able to be great companions first, but that as a breeder, you are not persuing other areas where your dogs are tested and you are knowledgeable. Right now, I have been titling my dogs in Rally obedience, getting CGCs on them, and am putting herding instinct tests on them in hopes of doing herding with them as well. I have two that I would like to put through agility and title them, though for me that is tougher as it is not as available around here.
But as you raise your litters, and keep pups in hopes that they will be good breeding stock, you will find that their personalities are so different that while all of them should be able to acheive basic obedience, some of them will be more apt at obedience, or herding, and others will be more athletic. So deciding what you are looking to breed for is great and necessary up front, but you kind of have to have some working knowledge in other areas so that some of your pups can be placed in homes where they will shine.
It is not up to us to make the dog be what we want, but to make what we want be what the dog is.
So back to getting a puppy bitch. Just because your contract states that you get your money back or a new pup if there is a problem (if that problem is spelled out, ie temperament, hips), it doesn't mean that you will be willing to give up the puppy, and you may have up to two years of expenses in the pup. So it is really a consideration when you go to buy a bitch. You may spend several years acquiring your foundation bitch.
As for expenses once she is two -- that means plenty of top quality food, excellent vet care and tons of training from day one, also entrance fees and costs of showing/competing with the bitch. Oh, and expect her to come into season at all the wrong times. But once she is two, you can take her to any vet and get pictures on her hips and elbows, or you can take her to a specialist and get the hips and elbows and other diseases screened for. I am in the process of that as well. Oh, that is not good to do while she is in heat or right after, usually about a month or so after she is done with her cycle. I have two girls going for their tests here in November. My estimate is over $500 and I am not complaining.
Another consideration is where to have the puppies. Some people have them in their kitchen. But healthy eight week old puppies will eat drywall, wall paper, linoleum, and they also make a ton of mess. I think a lot of times when people give up a litter, they were just not prepared for the amount of fluids and work cleaning. To me, though, this is the easy part. I built a room and built kennels and a puppy pen. I find that letting my puppies take themselves in and out on their own is really helpful. I use a doggy door into a special puppy kennel, and as they get older, I limit their indoor space, so that they naturally figure out that outside is a great place to toilet.
You will spend a ton of money if you do things right, just keeping it clean. But then too is advertising and screening buyers. Getting buyers can be a real problem for new people. You want your dogs to go to great homes, but what do you have to offer to these great owners? I am hoping that what I have learned and my experience in some dog-events will qualify me as somewhat of an expert. On the one hand, you have to sell yourself as well as your dogs. On the other hand, the propective owners will have to sell themselves to you. So expect to have increased phone bills, long distance bills through this. Give people enough rope and they will hang themselves, but you have to give them the rope. Usually telephone interviews are a great way to screen people.
Vet expenses may include an x-ray or ultrasound when the bitch is pregnant to figure out how many pups. I may include an x-ray afterwards to ensure a pup has not been retained (life threatening). It may include an emergency C-section -- haven't needed that yet, but know others with shepherds who have. Of course the pups need to be checked by a vet and given their first shots. Some breeders give their own shots, but I would not trust a new breeder (from a buyer's viewpoint) who is giving their own shots and not taking them to the vet. Much better to get the little health certificates and let the vet check them over. They may find something that you do not see.
If you are planning on having your own male, I would strongly suggest against it. But I have two males. The thing is, that all those things that could be wrong with the bitch, may also be wrong with the dog. But even if you have a decent breedable prospect in a dog, there is no guarantee that he will complement your bitch. No dog or bitch is perfect and we are trying by breeding to breed dogs that are as close to the standard as possible. If your bitch lacks some angulation, you will want a dog that has excellent angulation, not over-exaggerated. If the dog has small thick ears, you want the bitch to have properly sized and placed ears. You are not improving the breed, here. You are trying to improve your stock so that they are closer to what the standard is. By chance and with a puppy getting a dog that compliments your bitch is not impossible, especially if you are not afraid of some line breeding and are very well versed in the various blood lines. However, it isn't the easiest thing to accomplish.
BTW, you will have to have the room to feed and house all of your failures, until you are able to place them or just to keep them.
I am all for new blood in breeding. And I hope that you do persue this, but these are just a fraction of considerations and expenses you may incur in the process. I would not be surprised if I have spent sixty thousand dollars in the past six years between the whelping room, food, vet, puppy packets, food, training, entrance fees, kennels, cleaning materials, food, training, and vet care. I have a chronic kennel project going on. I have repairs to my house (due to the dogs) all the time. I am expanding my fences and always in training. So far two litters have netted me $3200, five bitches and one gift to my parents. Of those five bitches, maybe three have the potential to be breeders, maybe two, maybe 1, maybe none.
I am also not convinced that there are no good breeders out your way. (Of course I do not know and I am not calling you a liar.) But good breeders are not necessarily on the internet, or in the newspaper, or in the phone book. To find good breeders, you have to get involved in dog-activities, specifically GSD club activities if at all possible. And you have to actually find them and go out of your way to get there. But if you cannot find GSD people, then get involved with breeders of other breeds, they can still teach you a ton of pertinent information about breeding and maybe even sit with you through your first delivery.
The good news is that you have picked a great breed to get started with. It is a breed that has many outlets for your interests. It is also a breed that does not require docking or cropping, regularly requiring help in conception, or almost always requiring C-sections. They are much hardier (the puppies) than toy breeds that are very delicate and often have single or very small litters.
Our GSDs often have huge litters, so be aware of that too. It is good to go into a breeding with a healthy waiting list and some deposits. They have long skinny bodies and heads that do not usually create the complications that say bull dogs and bostons have. They are pretty hardy, not requiring a lot of temperature control, etc. And generally (at least from what I have seen) the momma's make great mothers. This is huge, because the amount of time you will spend saving a litter that needs to be tube fed for whatever reason is significant.
Good luck. And welcome to the site.