Just so you know the ones that run around $100 NEW ( I know that is not what you are asking for) but those that do run around $100 new. I have one and it is no good more than a couple feet away. It says it is good for like 100 yards or something but if the dog gets more than 20 foot away you are pounding sand.
The one I bought was similar to this. I don't know if it was even this brand or not but
http://www.petsmart.com/global/produ...=1110840514830
the one I bought was worthless over 20-25 feet. Inside of that it worked great and I could use it in the house to break the shepard of some bad habits when she gets to come in.
I can ask the dog. " do you need the collar" and she starts behaving. If I get the collar out I don't even have to put it on her or say anything. Just showing it to her is enough. She is a quick learner.