I'd say closer to $9K.
There is a used car dealer out in Powhatan selling a 2003 325iX wagon for $10K.
As of yesterday me and the wife picked up a 2000 323i wagon from a Pearson dealership for just $8k - and that's retail.
Any of the mods you can switch out for stock parts and sell seperately will better recoupe what you've spent on the car.
As we all know upgrades and mods actually add very little to the actual value of the car.