I wish more people would take inspiration from you and think about the consequences of adopting a pet before doing so. Unfortunately, most people seek help only after they took over responsibility for a pet and are facing problems, which is reflected in the amount of material available online or in book stores.
Unfortunately, I'm not aware of a book that covers all the things you should consider before adopting a dog, so let's walk through a few thoughts here:
The breed
This is a topic that most people fail to consider and that causes a lot of suffering for dogs because their owners cannot or don't want to provide them with what they need to be happy.
Most dog breeds can be placed into certain categories like:
- Toy breed (the traditional pet dog)
- Hunting / scenting /sporting breeds
- Herding / guarding breeds
- General work and service breeds
A full list of breed categories and their respective breeds can be found here.
Not all of them are obvious. Chow Chow, for example, is one of the oldest Toy breeds, but the cute and popular Westie (West Highland White Terrier) is actually a Hunting dog, bred for its fiery temperament to dig out and eliminate nests of rats and other burrowing rodents. Depending on their breed, dogs have different needs regarding training, walking, play time and an actual job to do (like herding).
You should think about your daily life with your dog:
- How much time do you have to actively train and walk with it?
- How much room does it have move around? A crate, a room, a whole house, a backyard or a whole ranch?
- In which environment would the dog live? A city with many other dogs and traffic or the countryside? Are there neighbors around with kids, cats, dogs or other pets? How hot does it get in summer and how cold during winter?
Read about different dog breeds and their requirements and characteristics, then compare how such a dog would integrate into your life.
A dog's breed doesn't decide its personality, but it gives you a guideline to how much energy and temperament it probably has.
For a first time dog owner, I strongly advise against working breeds like the Australian Border Collie. You simply don't know what you're getting into...
Where to get a puppy and which one to get
This is a very complicated question. On the one hand, you have the chance to literally save the life of a shelter dog. On the other hand, you don't know how much the behavior of a rescue dog might be (negatively or positively) influenced by its past experiences. But you might find a very calm dog (read: past teenage) or at least one that's already trained in a shelter. In most cases, shelter dogs are desexed, vaccinated and chipped, and even purebred dogs are available for lower costs than a puppy from a breeder.
With a puppy, you should find a breeder who socializes the puppy with humans, other dogs and pets, and everyday situations like climbing stairs or avoiding traffic or dangerous wildlife (if that's relevant to where you live).
No matter where you want to get a dog from, you should take your time. Visit the breeder or shelter and have a look at the available dogs. If you prefer a calm dog, don't take the first one that comes to you (those tend to be the curious and courageous ones that get into trouble). Ask for 10 - 20 minutes with a dog to assess its character and compatibility with your lifestyle.
Have a look at this video that shows simple ways to assess a dog's personality. If you live near a loud street, you don't want a dog that shies away from loud sounds. If you're new to raising a dog, you might want one that's submissive and doesn't fight being held down as much as shown. If you want to take your dog with you every day, you want one that isn't intimidated by strange objects (what the little guy in the video demonstrated was very good).
There are other videos like this one that explain the character tests and the puppies' reactions to them in more detail. This one compares puppies' behaviors (Please note that every time he says "it's not bad" he means "training this puppy is harder than average"). And here's another video showing how to assess the character of adult shelter dogs.
Finances
Next you should be aware that every pet costs money. Not only is pet food expensive, you also have to pay for annual vaccinations and irregular vet visits. Depending on where you live, you might have to pay more taxes and insurance might be obligatory or at least recommended. Also, puppies love to chew things, especially things like leather items and shoes.
As a rule of thumb:
- Bigger dogs need more food
- Higher quality food tends to be more expensive
- Pure bred dogs tend to have more medical problems due to inbreeding
- Medical costs tend to spike at the end of a dog's lifetime
If you don't plan to breed, you should make a plan to desex your dog at the appropriate age. This verifiably reduces the risk of cancer in females and gives males a more calm and tranquil personality.
You should also get information about additional costs like public transportation tickets for dogs (if you don't have a car), entrance fees to dog parks or similar facilities and dog training courses.
Training
You should start training your dog 2 - 3 days after you adopted it. This is especially important if you have a young puppy, because then you still have the chance to shape its personality and character.
There are countless books, blogs and videos available regarding this topic. I cannot recommend any one resource, because I think none of them gets the whole picture. I recommend reading a few different resources before adopting to get an idea about how training should ideally work and then returning to them once again after a few weeks of training to reflect on your own experiences and maybe get some ideas about improvements.
When it's about learning the body language and behavior of dogs, I personally prefer video material over written material, because you can only learn to recognize certain gestures when watching them. Again, I cannot recommend one single resource, but just searching Youtube for "puppy training basics" or "dog body language" yields a ton of useful results.
My personal tip: stay clear of video titles that contain numbers, like "10 things to know about dogs" or "16 useful clues to understand your dog better". Those tend to be click baits with superficial information and questionable content.