I paid $250 installed for my Crimeguard a couple years ago and that includes keyless entry. $200 should get you a decent one installed. You don't wanna do the installation yourself unless you really know what you're doing. You could end up with false alarms out the wazoo or the alarm not working at all, or the starter disable disabling the car all the time, etc. Best to have a pro do it.
You won't be able to touch a Clifford for $200. The current version of my alarm, the Crimeguard 533i3 is going for $150 at Crutchfield. Figure about another $100 for installation.
If all you want is keyless entry and basic alarm then the 328i3 from Crimeguard, $100 at Crutchfield, should do the job for ya.
If you want more features, like remote windows, sunroof, telephone access to the car (dial 800 number, enter pin, lock/unlock/start/windows via the phone), etc., you'll wanna look at those Clifford alarms.