in all honesty, the more mods you put on it, the less willing the average person will be willing to buy it. keep it as stock as possible, nothing is really going to raise the resale value enough to make a difference.
are you losing coolant at all? look at the underside of your oil filler cap, is it milky a little? those are signs of a failing LIM gasket. also, could be an external leak, check around the engine mating surface of the LIM and see if there is any seepage or build up. if there is, clean it off, then run it for a couple days and see if it comes back.How do i tell if it (LIM) needs replaced? how much will this replacement run up to?