To fix or not to fix

[adhesivo]

So my car is 10 years old, 90K miles. I thought it was in pretty good condition (no rust, no crashes, car feels powerful).
Today I took it for a full inspection at a good independent BMWshop. It turns out it needs new control arm bushings, inner boots, radiator hoses and most important, it's leaking oil from the valve cover gaskets.
If I add up all the repairs the joke turns out $4K. Then put new tires in the car, sparkplugs and oil and we are at $5K to keep the car running. Which is a lot of money for a car that is not worth a lot anymore. So I could:
- let it stay (not safe but cheap until it dies)
- fix it (expensive and we haven't even really touched the engine -valve stem seals?- or transmission)
- sell it (get rid of it and get a "better" X5)

What would you guys do?