from what i know you basicly haggle .
they will fist give a daft offer and you basicly just say "no i paid far more than that"
but saying that
my friends just bought a vectra from men for 500, two weeks later the wife wrote it off and the insurance company declared worth at 750 . so he was fine.
then they gave it back to him for 50 . and its only a 250 repair bill from a indipendant garage.
so hes again laughing
but they go on the basis they pick a low priced gtv and offer you that money
we all know cars prices varey and that the same car can be found at 500 - 1000 so they offer 500 and most people go for it with knowing to keep on at them for more money
the company should explain to you how you can buy it back , and i really think it is worth you doing this ,
just think of all the bits you would want back .
tax, battery,fuel,engine. etc etc
you probaly need to ask about how to get it back just incase they dont make it ovious