Do you already have factory power door locks? If so, you can probably find a Crimestopper CS-845RKE keyless entry system on eBay for about $45 shipped. I didn't have factory power door locks, so I bought a couple actuators, that keyless entry system, and a siren(so I could have the chirp chirp sound >

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I installed it myself and it worked great. The unit has some nice features for the price, and has auxilary outputs.
Also, I can help you out installing it. Just search for some answers, and if you don't find what you need, write up a new post. I've posted a lot regarding this before, and I think maybe soon I'll write up a sticky on alarm installations. >

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