Are you considering a puppy or adopting an adult?
If a puppy, it would be unconscionably irresponsible to bring a puppy into a home where the pup is left alone most of the day. A puppy needs full time interaction, socialization, training, metal stimulation for the first many months, or individual dependent, years.
Some people manage it with full time day care - but then a very real worry is that the pup often does not bond with you, rather it bonds with the sitter. (I see this in our Hundeschule now. The dog is amazing with the sitter but a nightmare with the owners who now and again show up on weekends.) In such a case you have an adult dog who really isn't fully 'yours' - and you have to start from scratch re-training, re-socializing, re-bonding.
If you are thinking of the full time day care route, also be aware of the expense. Sending a very young pup to a multi-dog day care facility is really not recommended as the pup would not get the attention it needs, (and often impossible because the dog is still entire) so you would be looking at hiring someone as your full time employee for the first X months.
A puppy is a 24/7 commitment. If you are not available 24/7, a puppy is not for you. Perhaps consider adopting an older dog.
I do know whereof I speak. I've told this story before, but it bears repeating:
I was a career-driven workalcoholic, working round the clock, traveling constantly on business. I did not have the time left over to properly care for a potted plant, let alone any sort of sentient being.
Out of the blue, my MIL arrived on my doorstep with a surprise. A puppy. Whisky Tango Foxtrot? What in the name of all that is holy was I, the never-at-home-workaholic, going to do with a puppy?
On the other hand, what would the fates have in store for that poor puppy if I gave her back to a woman clueless enough to buy a puppy as a surprise gift for someone whose life was wholly inappropriate to puppy-rearing? Worse, what if MIL gave the puppy back to the (insert expletive here) breeder who was unethical enough to sell the puppy knowing it would be a surprise gift to an unknown third party?
Poor poor puppy. After such a questionable start and with a questionable future looming I couldn't let her end up in the wrong hands.
So... I called in every favor I could, spent every extra penny finding a solution. My sainted retired father came to stay at my house most days, I hired a puppy sitter for the times he could not help, OH and I staggered our working days so one of us could be home whenever possible. And of course every single free moment was dedicated to the puppy. No dinners out, no non-puppy entertainment.
But that wasn't enough. It quickly became clear that I had to drop out of the corporate race if I was to do right by my puppy.
Even though I had the day covered so that my pup was never alone, that wasn't the same as being with me, socializing to my life, my ideas of training. And it showed.
I was lucky in that St Swimbo was one of those rather rare critters, an easy pup despite her poor start. But it could have gone so very, very wrong. Well, actually some things did go wrong, and I paid the price for the next 15 years.
Sooooo... please, think carefully. Do not get a puppy unless you are in a position to give it the time, attention, socialization, and training necessary. I'll say it again - a young pup needs someone right there, on the spot, 24/7.
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If you would consider an older dog, one whose character is known and who is has proven to be OK with being alone for some hours, that might be a possibility. But again, you will still need some form of dog care. An adult dog will still need mental stimulation througout the day, and certainly must have a chance to empty his bladder regularly. Here you might consider doggy day care, or a sitter who comes for several hours. The right individual must be carefully selected to fit into your situation.
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However - a dog with separation anxiety must not be left alone as you anticipate. Separation anxiety can be worked on, but it is not an easy or quick road to a solution. The question I have for you:
What if you got your dog and then found out that he had separation anxiety? What if he destroyed your house, if the neighbors lodged complaints against you? What would you do then?
If the answer is 'give him back to the shelter/breeder' then in the strongest of terms dog ownership is not for you.
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Sooooo - to recap: Given the scenario you describe, no - you should not take on a puppy, of any breed. Rather if you think you could provide a good home for a dog within the framework of your current commitments and lifestyle, consider an older dog, a settled mature adult or senior, one whose past and character is known, who has undergone assessment and has been found to likely fit into the life you can provide. And you must commit to providing that life, to meeting the dog's needs, no matter what else is going on in your life, now and for the rest of the dog's natural lifetime.
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Towards that end, as you are mulling over your suitability to dog ownership, have you done the SKN Theory course? If you are a first time dog owner, get that done before you go any further. The course is designed to get you thinking of these issues upfront, before you make that 15+ year commitment.
Once you determine that you can indeed offer a dog all that he needs, for his entire lifetime no matter what the winds of fate may blow into yours - only then should you start thinking about breeds or mixes, only then should you start your search for the right individual.