* Be sure of your requirements. Consider how much time you can spend with a pet dog. How large is your home? Are you looking for a watch dog? Consider questions such as these before making a decision. Don't bring along a pup just because it was looking prettier than the other puppies.
* Be ready to pay. You may need to spend heavily on vaccinations, visits to the vet, licensing, dog food, accessories and many other anticipated or unexpected expenses while bringing up a dog.
* Go for aged dogs. You are quite familiar with the older dog behavior. Therefore, it is always advised to go for old dogs rather than young dogs.
* Get training for handling dogs. May be you are a new pet owner and have never kept a dog before. Hire a professional trainer to train the dog and to train yourself on how to handle your pet. First of all the professional will teach you how to potty train your pet. Such professional trainers cost money. Be ready to meet such expenses.
* Diet. Learn from the previous owner or from a professional about dog feeding. It is important to have full information about which food items or dog food would be best for your dog and food items that you should not feed your dog.
There are various pet care books and literature available online and offline that can help you with the required information. Best of luck with your pet dog!