I am considering going tommorow to look at an older anvil that has lost its horn. Without the horn it weighs in at about 100#. Assuming all face testing such as rebound and lack of delamination are good; is this a worthwhile consideration. I'm figuring that I can use a hardy hole bick if I need to bend anything. I'm currently using a 12# sledge hammer head. The asking price is $200 US. Advice.

Yes, no, maybe it all depends on the condition of the face and whether its not a cast iron ASO.

One of my favorite anvils is heeless; about 120 pounds, with a face in great shape.  I generally like such anvils as they tend to be reasonably priced, (mine was US$40 about 25 years ago.  Sold to me by a farrier so he was familiar with the anvil market...)  US$2 a pound seems high for one with a catastrophic damage. Perhaps if the rest is in great shape....Sometimes one indication of abuse is just one of many and such items should be avoided---especially at high prices.

Does not look cast. From the pictures I have seen. If cast its deffinatly a no go. Pictures make the face LOOK good but I intend to check with ballpein and ball bearing. My question is more about how much a lack of horn would effect the anvil. As far as balance and use. Assuming the hypothetical that the face is in good repair with a decent rebound and no major dead spots or delaminatiins. 

The average anvils in my area are between 4 and 8 per #

The anvil I purchased a few months ago is missing its heel, and the balance on it is fine (not tippy at all), so I suspect missing the horn would be fine as well. The one I bought is 180# with a pretty good face, and I paid $0.66/LB for it, or 125$. Anvils may be more expensive where you live however.

I know missing the horn and missing the heel are two pretty different things, but for what it's worth, my anvil has worked very well for me so far. I don't regret buying it for a minute.

If you can post a photo of the anvil in question, that may be helpful.