Short answer: can an active, large breed working dog live in an apartment? Yes, I have known people who have done it successfully. However, a lot of these people have at least been hobby-level dog trainers involved in some kind of structured training outlet for their dogs. More normal lifestyles can be made to accommodate them, as well, but I would say it succeeds under very specific circumstances, and only with a great deal of effort (and knowledge) on the part of the owner. I also use "succeeds" in a very specific way- I mean turns out a well adjusted, stable, happy, fulfilled dog. It can absolutely go very wrong and land you in a bad spot with a dog who poses a real risk to others.
Long answer: the apartment itself is not what I'd be worried about...
There's a lot of levels to answering this question. First, let's talk about the timeline. College is a difficult time to have any pets, but especially a dog. Talking in terms of time commitment, it depends largely on the structure of your social life, your other interests, your time commitment to academics, your time commitment to possible work opportunities, and your ability to integrate the dog into other aspects of your life. Add to that that free time changes greatly each year, especially in the more academically rigorous colleges, and I think it gives food for thought. I say this as someone currently in college with two dogs of my own plus a third through my school, also living in an apartment. In my case, it works largely because my life is my dogs. I am studying to be a dog trainer/possibly for a degree in animal behavior, and two of my three dogs are service dogs in training that I can incorporate into daily life to a high degree. One of the three (the one from school) accompanies me every day to school.
Another concern at this stage is funds. Are you going to have the financial stability for a dog in college? Are you going to be working through college? What about taking out possible student loans to pay for college? What would you do in the event of a real emergency? I have had two major health scares with my personal dogs that so far that would have put me into debt had my parents not been able to help me out.
Second, the breeds your interested raise other challenges and questions.
For one, there's good chance housing will be hard to find, especially with a GSD, quite possibly with a Dobe (especially cropped/docked), and possibly with a Beauc (especially black and tan, cropped one), depending on the apartment complex. Breed bans are getting more common, and GSDs especially are a commonly listed breed, and often Dobes are as well. Beauc aren't, but the b/t ones have the look. Life during and directly after college can mean a lot of moving around. Taking on breeds often listed on banned breeds lists is a risky move in this kind of a situation, IMO. It's one of the reasons why my younger dog (who will be my service dog, hopefully) is a field bred (higher drive/energy) Lab vs the Mal or GSD that I was considering.
I'll also add in- these breeds can produce intense individuals. They are not easy dogs to raise, and are not breeds I would recommend to someone who has not had a lot of dog and training experience. How much direct dog and training experience do you have? How interested in it are you? What kind of intensity are you looking for in a dog? What is drawing you to these breeds specifically? Have you looked into lines/breeders at all? A lack of training, structure, exercise, and/or knowledge can very easily raise a scary dog when you're talking about these breeds.
I will also add- a stable dog of one of these breeds is very different than an unstable (under confident, fearful, anxious) member of these breeds. When people are considering a breed, I often suggest they consider the possibilities of what happens if the dog they get grows up to show aggression or reactivity. This challenge is compounded in an apartment, where there is a dense population of people and dogs, and a lot of outside noise, which a guard breed will almost definitely react to in some way.
As well as possible temperament concerns from poor breeding, there's also the concern that GSD and Doves have serious health concerns. The biggest concern in GSDs is hips, and in Dobes there is a very pressing concern with heart issues. To my knowledge, Beauc tend to be pretty healthy physically (though there should still be the breed-suggested health tests, which can likely be find on the breed club's page. I'll talk more specifically about them below, though.
It is absolutely necessarily to go to go to a reputable breeder health testing their dogs. That's not cheap, and I would expect to pay at least $1500, and probably closer to $2000-$2500. I feel confident in this estimate for GSDs at least, though I know Dobes less well. Certainly would be surprised to see a reputable breeder selling either for less than $1000, though.
I will also add- if you're not an active person now, don't bank on an active dog suddenly changing the way you live your life. I do have higher energy dogs because it helps get me out of the house, but I'll be the first to admit that that lifestyle change is hard and doesn't always work.
I absolutely would not recommend relying on a dog park for exercising any of the three listed breeds. All three tend to be more domineering in interactions with other dogs, especially unknown ones. Their play styles are very physical, and they tend to be rather high arousal/energy dogs that can struggle to keep their play at a safe/appropriate level to be playing with an unknown dog in a chaotic environment. Add in the possibility that they have not been adequately exercises prior to going to the park, and you may just have a recipe for disaster.
Expect exercise for these dogs to look like environmental enrichment at home (food puzzle toys, meals frozen in blocks to make them work at it), training sessions, physical play (could be a good tug game with set rules and incorporating obedience, or could be something like a structured game of fetch, depending on what the dog likes best), as well as pure physical exercise like walks/running. These are not the dogs you come home to at the end of the day and just sort of sit around with. They require quite a lot of work on your part, and not meeting their needs can mean destructive behaviors and a lower threshold for reactivity/aggression in a lot of cases.
Now, talking more specifically about Beauc- there is a relatively small gene pool in the US currently, and there aren't too many big name breeders in the game. I have not been impressed with what I've seen of or heard about the dogs being produced by a lot of US breeders, and have heard of one very recent horror story regarding one of these kennels. A lot of people I know who choose the breed feel strongly that the safest bet is to import, which has its own complications and costs.
Overall, I think that the timeline is not one I'd recommend, and I would impress that these are all intense breeds that require an intense commitment, both in terms of cost and training/knowledge.
