How does replacing an engine impact the resale value? Add? Subtract? No difference?

Not knowing the price makes it hard to determine if its priced correctly. For me its pretty simple, It lowers the price and I would keep looking. Something has caused a complete engine failure, there are too many unknowns on this SUV. No maintenance records or engine replacment info, make it hard to tell how the rest of the SUV was taken care of. Also the new motor could already have 200k+ miles on it. Another one will pop up unless they are giving this one away.

I would put a negative on price from what your question states, no info on when, where, and no receipts. I would not buy it personally unless it had a recent receipt of a genuine Ford crated engine and where it was installed. Note: family negative experience with similar.

The mileage on the new engine can be found in the engine bay. My 2011 Sonata was replaced with a 2013 engine. The 2011's had problems. My car drives better and I have no reason to think its a negative as long as we keep track of the miles from install date.