I know what you're saying about prices being all over the place. I found that out when I was looking for Winnie three years ago. I found the individual seller asking prices to be lower in the East. I gathered my information, thought through the owners asking price and then made him an offer that embarrassed me. He didn't accept. I stayed with my offer. One week later he emailed me that if I was still interested he would sell to me at my price. In three days I was in Arizona and ended up driving the unit back to Texas.
Note: if you are not embarrassed by the offer you make, you are offereing too much money. That is my two cents. Best of luck.