A few questions, need help

My wife has an 03 Sebring LX sedan. We bought it used a couple of years ago with only 10k miles, but used none the less. She wants me to put a remote start with keyless entry on it for her. I'm fairly mechanical, so I'm sure I can do it. I just need a little help with the stock wiring. Here's my questions:

The car did not come with keyless entry remotes (but it has electric windows/locks). Is there a way to determine if the car is already set up with keyless entry, and I just have to buy the key chain remote?

Where can I get a wiring diagram online? The dealer wants $50 for a wiring diagram. I'm going to need this when I hook up the remote start (especially if I have to install the keyless entry also).

Thanks in advance !!!!!!!!

you can get the wiring diagrams from bulldogsecurity.com. If you have the grey chip key the you have to have a spare key and a bypass module so it will start with a remote. They are time consuming to install will take a good eight hours or more it depends how easy it is to get to the wires you need to splice into. Don't know about keyless enrty most have them from 97 up dealer charges about 150.00 dollars to do programing I think.

Thanks for the reply !!!!! That site had the wiring diagram and was very helpful. The dealer is being a total a$$ about the keyless entry. He tells me "the car probably has it, but you have to buy a controller and have us try to program it to find for sure". I'm not spending almost $200 to find out IF it has the keyless entry. Not to worry though, that dealership has lost our business forever. Ford has a site that you can put your vin # in and it will show you the original invoice of the vehicle with whatever options it was purchased with. Does Chrysler have something like this?