If it is in decent shape jump onit. Those engines are like mini North Star's. They can consume some oil and burn some but theya re preety durable if you can put up with the leaks and the oil burning. The Olds Auroa had some really good structual designs a lot of what GM use's today in terms of their platform designs where developed onthat chasis. For the time it was a huge leap forward for GM interms of chasis regidity and torsional strength!
I would take the car and I would do the following. I would purchase 2 bottles of Auto-Rx. I would put 1 0nce in the power steering, 6 onces inthe transmission and the rest int he crank case. I would drive the car for 1200 miles and then get the filter and fluid changed onthe transmission and I would drain and refillthe power steering. After about 3000 miles on the Auto-RX inthe engine I would drain put a new filter on and refil with another cheap oil. I would do a 2000 miles clean phase then I would switch over to sythetic. I would go to something like M1 0W40 or M1 10W30 HM and I would change the filter twice a year and the oilonce a year and that engine will out live your desire to ownt he car assumeing the gaskets hold out. I would put Walmart brand Dex-VI in if you change the fluid and filter if you have the dealership do it they should already be useing that and you will probably never have to touch that transmission again for atleast 50,000 miles maybe 75,000 miles!
That car should have alot of life left in it. Usualy cars owned by older people that have low milages have a lot of deposits in them from slow driving, lots of idleing and lack of maintence. You should be able to put 200,000-300,000 on that car assumeing the gaskets hold. If you need to change the gaskets or injectors at some point it is a small price to pay for a free car. These things for the time road nice and had good performance!