2003 Civic-Dent repair and transmission?

[Bill]

Honda Experts,

I'm considering buying a 2003 Civic with a couple of minor problems I
would like to ask about.

There is a dent in the rear door, from hitting something, it's a 4
door. The dent is about 18 inches square, but only about a half inch
deep.

Question: How are dents like this usually fixed? Would they do body
work on this? I assume; put filler in it and repaint it? Or would it
be better to replace the door? (or possibly the door shell) I see
doors are around $300 to buy.

Also, the paint on the hood is flaking off. It's just showing black,
bare metal below it. What I think has happened is: I think they put a
third-party part on it, probably a cheap hood, made in China, after an
accident. It probably looked mostly normal at first, but after 2
years, the cheap paint started flaking off. It's also not quite the
right size. It's close, but doesn't line up.

Other thing; I've read that the automatic transmissions on these cars
have a higher failure rate than normal. Or is that only the 2001 Civic
that had a high failure rate? Any thoughts/experiences with the 03
transmission? How can I check it to make sure it's working correctly
when I buy it?

I suppose this won't get as good gas mileage as my current 97 Civic LX
with manual transmission. I got 37 mpg on a road trip this year.

It does have a salvage title, LX, and 110,000 miles

Thank you,
Bill