Vintage Bottles

In my newest won unit I have a dozen or so very old looking bottles. Does anyone have knowledge or a source for me to be able to determine if they have any value? I matched a few on eBay in the 10 dollar range, but I don't count on eBay to be completely accurate with these kind of things.
 

Glass is tough. I got a ton of glassware in my last locker too. Some dating back to 1925. I have a friend who is very good with recognizing glass who I use to help me price out stuff. He typically talks about the origins of the bottles, the story behind them, etc. when I bring bottles to him. If a bottle is related to the medical field, or beverage industry (of course) it brings more. Mason jars and such not as much. Apparently glassware and bottles that originate in Indiana are more desirable to collectors than others. Any markings or anything on them?

I've run into the same thing.  No advice here, sorry. 

I was just at an estate sale and these two guys were going crazy over the bottles.
He had one and was saying how rare it was.  Next to it was one he said belonged in the recycling.
They looked identical to me!

Same with Lab Glass.  I can't tell new from old.  One estate had stuff marked between $20 and $A-sh*t-load.
It was being grabbed up like crazy.   

The stuff at he university's surplus store looks identical, sells for $2-&5, and sits there....? 

Ok here's the deal with old bottles, very general guidlines
MOST bottles made after about 1910 are worth recycling. If you look on the side, there's a seam. If the seam runs to the top, its machine made. LIKELY little value. Bottles made in a mold and hand blown are much more scarce, as a machine outpaced hand blown by x1000.

Older bottles can range from $3 for a very common, to $50,000 for a super rare histic flask depending on color, rarity, condition, ect. If you have something you think may be good, post a pic at antique-bottles.net or check a pricing guide at a book store/library such as Kovels.

Most people don't know bottle collecting even exists but there are a lot of collectors and a lot of money in it.