1995 Toyota 4Runner Oil Leak, Rough Idle

Little over a week ago I bought a 95' 4runner, V6 3.5L, 4WD, automatic transmission with 115,000 miles on the odometer. The previous owner told me that he had the head gaskets and timing belt replaced about 20,000 miles prior and new tires. Etc. I test drove it and had my father, who is somewhat of a mechanic but not enough to have me asking questions elsewhere, inspect it and figured for the price it was a good buy. I was noted by the previous owner that it had a SLIGHT oil leak which I stupidly shook off as merely a quick fix. Now it's 6 days later and i'm experiencing drastic oil leaks and a rough idle which runs about 500RPM at a stand still. I am a poor college student and don't have the extra 1-2k to fix it if it's a major problem, please help!