Nice! How much did you get it for? It looks like a stock S4 with some strange mods... The roll up windows have S5 door panels (stock turbo did not come with manual windows), relocated battery, coilovers, crown vic meshies, and it also looks like you got camber adjusters on the back because FC's usually have huge camber when lowered, but your car sits fairly straight...
Welcome to the club man, now order some carpet!