bahador

I want to buy my lease but before they give me a price they want to check it to give me a residual price on it but I have it lowered,on rims and system installed.My question is when having them determine a price do I have to return it all back to stock..have them generate a price and then if I want to buy it install everything back on..Also I have quad exhaust that I want to install but I am waiting for some advice because this is very important.

Thank You brothers