Value is always the same: how much are is either party prepared to "give" in order to "get".

Price is something else.

Wolf gave the best advice back several posts back. If seller is as upfront as everybody, for some unknown reason, figures, ask for photos of the other impact areas.

You want to see what the bottom of the left fork and the left swing-arm looks like. Ask to see as many pics of the left side as the seller is willing to send you.

Ask if the accident was reported to insurance. Most likely it wasn't, as I'm pretty sure the bike would have been totaled because of the frame damage. Remember, if you have to do a safety check (I would have to here), it may not pass once it is yours: get the information; print the emails.