A guy close to me is advertising a 68 455 motor including the carb and everything for $695, is that a good price for a 455 of that year if it's in good shape? What are some things to look for during the purchase?

 

That isn't too bad. You will want to check the heads to see what casting they are. C heads are decent heads. If it is J then the 455 is low compression from the mid 70s. I am not sure what letter would be on a 1968 455. If it has E heads you should buy it and sell it to me.

 

It depends on a lot. Is this a running engine that you can hear before purchase? Is is stock? Modified? Is there documentation on the actual condition of the motor? If it's simply a core that will likely need to be rebuilt, that's too high. If it's a solid running motor that you can verify, it's a good price.