I noticed that car last night, I sure would like to have someone who knows what they're doing check it out before I made a bid on it. If the water was high enough to get sucked up into the engine, I would think it was high enough to be considered a "flood" car. In other words, high enough to get into places water should never go.
If the water only killed the motor, and did nothing else, and they're willing to let it go for a little less than the "buy it now price", it might just be a good deal for a back yard mechanic.