It appears that the owner of the property we're trying to buy from a) doesn't really care to sell it, b) doesn't see the value of dotting i's and crossing t's or c) all of the above.
UPDATE: turns out is was a much simpler (mundane) reason: jet lag
He'd just landed from a trip to Europe when he mis-marked the counter to the counter to the counter. Our offer has been accepted. Now we just have to see what the inpsections turn up tomorrow (pest) and Monday (general home).