Suckered is a relative term. I wouldn't expect much more than a rolling chassis for $450. Looks like the car has seen some salt, in my part of the country that level of corrosion isn't unusual on a 20 year old car. If the body and interior are in decent shape, I'd say you still did well for $450. You'll have some work to do no doubt, maybe some new O2 sensors and some new wires / connectors / sensors here and there is all I can see from here. That plug is just an inspection cover for the flywheel / flexplate, not a big issue.