If you can't afford a trainer, (or even if you can) you have to be willing to
put in the time and consistent training. Have you ever tried clicker trainin?. I highly recommend it. But very very important that you read and learn the proper technique for using it. There are dvds that are v ery good that are step by step. I swear by clicker training.
Aggression and Reactivity: Research, Expert Advice, Tips | Karen Pryor Clickertraining