Did somebody already suggest to change all the fluids on the car?
Maybe remove the valve cover and check for black sludge and run some seafoam to get the systems going again.
Then when you are driving it, watch the main rear seal and other seals, they may be dried out and start leaking.
This is a concern for basically all rubbery things under the hood: vacuum lines, fuel lines, water hoses fan belts (well those don't leak).
Last but not least, take all brakes apart and replace the worn parts.