Your calculation is right except it's OMV * 130% and not PARF.
Your depreciation is high for 2 yrs plus becoz you bought at high
price. The idea is to push the price as close to paper as possible,
or dun go thru dealer.
And there may be additional money back from the car body (depends
on make and year). For examples, the dealers say the 2001-2003
Sunny fetches 6000-8000 for the body. Dunno if true, maybe tio
smoke...