OK, first, I would recommend rescue if you don't want to pay for a pup from a good breeder. With a rescue dog, you basically know what you're getting when you meet it.
Secondly, and don't take offense, a Rottweiler is a VERY powerful, dominant breed that will CONSTANTLY challenge you, and from your post it doesn't seem like you understand the temperament of the breed. Rottweilers need a job to do, to thrive and keep them level-headed. They're a true working dog, and definitely not an indoor house pet.
Don't get me wrong, they're fantastic dogs, but unless you're ready to make a lifetime commitment to TRAINING, TRAINING, TRAINING, (And I'm not just talking "sit, stay" type training.) and socializing a WORKING dog, I don't think a Rottie is for you.
If you are willing to make that commitment, and are prepared for a VERY rocky ride (particularly if you keep your male unneutered) then I wish you luck!