Honda Civic LX 2007

Hello everyone, I just bought a brand new Honda Civic Coupe LX 2007 with manual transmission about 4 Months ago. It was straight from a Honda Dealer in New York. Right now it has roughly 800 miles on it. Everything else is just the way it was when i bought it. There are no dents or anything like that. I have been thinking about trading in my car to get a Honda Civic Si. I am wondering how much i would get for my car from a dealer who accepts trade-ins and buy a new Honda Civic Si 2007-2008. I know it all has to do with where one is located, but I'm asking for a generalization of my car's value. If you were to go online and look up a Honda Civic Coupe LX 2007, the specifications match the ones of my car. I have not added anything to the car, or taken anything out. If someone could help me out here, I would really appreciate it. Thanks