1995 Pontiac Grand Prix v6 help!
 

I am looking at a 1995 Pontiac Grand Prix SE 3.1l v6. I wen to look at it and the guy said the only problem was a bad Intake Manifold Gasket. However, there is water in the oil which leads me ot believe that the Head Gasket is what is bad. Is it possible for a bad Intake Manifold Gasket to cause water access to the oil? I need to know 100% what is wrong with this car before I buy it that way I know how much money I am putting into it. Any advice helps.

Thanks, Lacy