In addition to what Padgett says: As values/prices continue to drop, there will be more and more people buying them that may not be able take care of them properly. As they continue to get "torn up" by people who buy them to use as "ricers," it will be the well-cared-for un-modified cars that will start to rise in value first. In my opinion, that won't happen for at least another 10 years. I suspect values of all will continue to drop for another 5 years, then plateau for 5 years before the good cars start rising in value.
So, enjoy them now and don't worry about what they're going to be worth in the future. If you haven't sold the car by the time the cars are worth a substantial amount of money, it won't be you enjoying the luxury of owning a valuable car, but your heirs.