Unfortunately for sellers we are in a time in history where prices are way down. Of course what that means for a buyer like me is that I can buy a nice late eighties and early nineties 5 series cars for somewhere around 2000 dollars. I am hoping to take a nice looking 1991 525i for a drive later this week and the seller is only asking 2500 dollars (which very possibly means he will take 2000).
Your car is certainly very low mileage, and for many cars that would be a great selling point. For a BMW not so much. My 89 525i has 300 000 km on it and uses no oil and runs strong. I was gonna do a leak down test on the engine and after driving it the tech agreed with me that there was no need.
What you have is a driver that will give you or one of your sisters great and long service. Work something out to keep the car in the family. You will not regret it.