keep in mind you may need a bypass mod as well.. most new vehicles (newer than 1998) have a factory theft system on them ..in case of dodge/jeep/chry etc they have a transponder system that, normaly, requires 2 key to program a mod to bypass it.
hopefully you know what your doing bc if not you can cause alot of damage to your vehicle and void any warranty w/ vehicle.
i sell these systems etc for a living (and have for over 14 years). i see ppl all the time that think it's easy and try it them selves. i know locally here no shop will install/warranty a system like this if bought/installed someplace else. if you have any doubts on installation have a good shop install it. it's worth the cost.
just to give you a idea @ my place a remote start w/ bypass etc etc installed on average costs about $260.
as asABSOLUTnie said you can find one un-installed for $40 thats normal uninstalled cost of a remote start, so not like your getting any kind of deal. keep in mind IF you can find a shop to install it most charge $75 / hour (some more/less) if i was to install one of these not bought @ my shop i would charge min of 3-4h labor + parts and after all said and done would cost more than a unit bought/installed by my shop, not only that your unit would carry no warranty @ all.
now if you know what your doing between the remote start & bypass you will probably have about $75-$100. multi meter & test lights will be your friend.. NEVER trust any print out for wire color's make sure to test them all.
Crime Stopper RS-1
basic 1 buttom remote start i sell @ my shop that works real well plus has extended range antenna