I bought a brand new SportDog 1200 on Ebay for under $100. 1/2 mile range and 8 level settings but I only use level 1 and I've used level 3 to deter deer and rabbit chasing on my bird dog.

On the 16 (or however many) levels of stimulation...you've got a high and a low. The other settings are just scattered in between. So if your collar has 6 levels and mine has 60, the high and the low are pretty much the same on both.

Read up on them. They've really improved my training but you can't use them in frustration or (as said earlier) if you can't see the dog. Nothing like shocking a dog that's on point. You don't want them to shy from point.

Good luck.