Corolla and Civics are more fuel - efficient in comparison to Accord and Camrys. It's a matter of choice, but I would go with a Civic, if I were you. The reason being, they are very fuel efficient and very easy to maintain. They also have  smaller engines, leaving you with more mileage on that same amount of gasoline you would buy for a Corolla/Accord/Camry.

In terms of reliability, your Honda or Toyota would easily surpass a 2000 Hyundai. Although it's an increased invesment, you would have a much better gain over the long run.

Tips on buying  a used car:

www.edmunds.com/advice/buying/articles/78387/article.html

www.faqs.org/docs/consumer/used-car.html

Hope that helps! Good luck. Be patient and you will land yourself a sweet deal.