First off, let me apologize for any stupid questions. I am not a tuner, and I know nothing about the "scene"; hence the questions. And before anyone flames me, yes, I did do a search. The results were limited by my capacity to articulate the search in sufficient unambiguous terms. So, here it goes.

When one decides to "tune" a vehicle, what are the fiscal impacts on the value of the car. Do mods improve resale? Do they actually reduce the value of the car? I imagine it's a case-by-case basis, particularly on what has been modded. I understand that a tuner does not mod a vehicle for it's return value; it's not an investment. But I'm trying to get a better understanding.

What does a tuner do with a modded car when he decides to sell it? Does he pull the mods out? Does he leave them in? What's the likelihood that a set of mods for one car will fit the next car the tuner chooses to buy?

Next, how does he go about selling his car? Does he list it in the paper, or on a website, or what? Does he try to sell it to "tuner" acquaintences?

Where does one go to purchase a tuner vehicle?

The whole point here is, that it's plain that a market exists for tuning. Period. But is there a market for the final product? Is there a place, or are there channels through which an individual may purchase/sell modded cars?