if you dont have crap then your looking at about 700 or soo dollars.. i was looking into replacing everything on my car too so i had everything new for the a/c... evaporator core, dryer, condensor, expansion valve, lines, compressor, and if you fill it with r12 then your looking at another 100 there too, cause someone with have to evacuate, vacum, then charge the a/c system. all in all if you have nothing, then your looking at a grand.