I installed an Autopage RF-420 on my 1997 Civic EX when the factory alarm crapped out. All in all, with battery backup, the autopage SIS-12 sensor, and an additional siren, I paid right at $130 for all the materials and did a stealth install myself.
The alarm itself was about $80. It doesn't do remote start, but, I don't need that feature. My main goal was to protect the car from getting boosted. Next time I rip the car apart, I am going to install a hidden kill switch or two. Overkill, probably, but the car has sentimental value to me because it belonged to my wife who died in January 2007.