Mruby1987

Hi everyone, nice to meet you. I'm Matt.

So, I am on the fence of purchasing a 1958 Plymouth. It appears that it is either a Belvedere two door sedan, a Plaza 2 Door sedan, or maybe a Savoy business coupe.
Frankly, I am entirely unsure. The current owner has added all sorts of Belvedere/ Fury trim (i.e. hood spears, Belvedere hubcaps, Sportone trim, etc..) and, naturally, has made it into a "Christine clone."
Now, this would be my first classic Mopar. I have owned a couple 70s Cadillacs before and I know my way around a car mechanically speaking. So, I am not afraid of getting my hands dirty.
I have yet to see this car in person as it is quite far from me, but I intend to go have a look at it this coming weekend. That said, I have some questions.

1.) Before I see the car, how can I tell the model> I have some photos attached from the ad.
2.) Not sure of the engine, but I am told by a friend it has a 318 with a single four barrel. Anything I should look for? Common failure points, etc?
3.) When I drive it, what should I be listening/ feeling for?
4.) I'm aware parts are expensive on these cars (which is fine) but, what are some common failure points? I already have a rough idea of rust areas to look at (above headlights, dog legs, behind rear wheels, bottoms of quarters, and rockers) but, any others?
5.) I am not sure if I plan to hold onto this one, I am seeking a Belvedere sport coupe ultimately. This one might end up being a flip.
6.) Current owner is asking $20k. What are these worth? Approximately, of course, seeing as I am unsure the exact model.

Anyway. Sorry for all the points, I am genuinely excited to check out this car and get into the world of classic Mopars!
Thanks everyone for your help and advice!

~Matt