Before you get your dog, thoroughly research your chosen breed. If you pick a retriever be prepared for it wanting to retrieve, if you choose a sight hound be prepared for it to chase things in the distance, if you decide on a collie, realise what it will need to keep it occupied.
Choosing the right dog and starting training straight away gives you the best chance of being able to reward your dog for being a rewarding dog.
The majority of behaviour problems can be helped/cured or managed with a good understanding of why the dog is doing what it does. I can help you learn about how dogs think, what their body language is saying and how to keep your dog at a level that means they can still concentrate.
A dog that is too stressed or excited will not be able to focus on you or listen to what is being asked of it. However with careful planning they can learn to cope and offer different more appropriate behaviours in these situations.