I am looking for the perfect dog?

My dog, Rocky was hit by a car in Augest. His boyd started shutting down so we had to get him put to sleep . That was the hardest thing i have ever done and i miss him so much. I miss having a dog run around the house and make me happy when i was sad. So i am finally looking for a new dog. I want a dog that is small but isnt that expensive. Do you have any ideas ? any breeDs?