I pick a lot of bikes and items here in the mid west! When with them, take in the whole area, not just what your after. Get them talking about the general things. Slowly steering them toward what you want thru the general conversation. Doing this, you can usually tell alot about them and their habits. Things like if they watch to much TV, or they have an Uncle Benny that thinks he's an expert on life and pricing old stuff, and of course, the dreaded "I looked on Ebay" line! MOST IMPORTANT!! get them to price it!!!! usually in a real deal, picking situation, the one who throws out the first number looses, this will tell you where they are at. This also helps you avoid an accidental low ball offer, and sometimes nets you a killer deal!!! The only times I've really gotten involved with offering to low, is when the bike is hanging. In a lot of the barns these old boys tend to hang everything sky high!! Never offer near your top dollar till you can see the whole bike or item. It can look good from the sides and bottom, but have real issues (paint ect.) on the ground. You can always go up! But can not normally go down.
Just my 2 cents!