Vehicles, unless rare and highly sought after... and generally in factory stock condition.... will NEVER be a good investment. Modifying them will almost always be a guaranteed money looser.
Look at it like this... without all of that crap added to it, how many prospective buyers do you have? Tons... anyone looking for a NICE affordable 4-door car that's in good condition. Once you pile all of that sh!t on it... who are your prospective buyers? Only people in the previously mentioned group that like 20" wheels, lowered cars and big stereo's (AND, they have to LIKE the stuff you've added; modifying cars is more personal taste than anything else)... everyone else will be immediately turned off. It's called supply and demand; you have the same supply, but by changing it so much, you've instantly decreased demand exponentially... which means what you've got into the product... you'll never get back.
If you're lucky, you might be able to sell it for $500-$1000 (I wouldn't bet on anywhere near the higher end of that ball park) more than the going rate for the same car in factory stock condition... interesting huh? Drop $3000 of aftermarket into a vehicle and when it's time to sell... you'll be lucky to get 10% $3000 of that back...
Almost always more lucrative to return the vehicle to stock and sell everything separate.