Looking at the pictures of the interior, in particular the seats and seatbelts, it would appear as if the water level went at least as high as half way up the seats. I would think that at the very least, the carpetting and padding would need to be replaced. Who knows what may be lurking and growing in the vents.
As it won't run due to a bad ECM, the water must have at least reached the level of the airbox. How long was it under water? Is the ECM the only reason it doesn't run? What other electronics got destroyed in the process? Is the crank full of water? The tranny? I'd be nervous paying the $4,550 current bid for it, which does not meet the reserve price considering the potential unknown problems.
Black 2000 SSEi, Silverstar Headlights, Angel Eyes fogs, 3rd brake light overlay, hi-flo cat, drilled 180 degree thermostat, Intense FWI, PCM, shift kit, and 3.4 Pulley. Solid front mount.