Alexander N. Pandis lived high-- plunking down $32,000 for a Rolls Royce, jetting to Paris -- but federal prosecutors say he made at least $500,000 from such scams as selling rare musical instruments he had borrowed.

Pandis, 25, of Chicago, pleaded guilty this week in U.S. District Court to mail fraud and credit-card fraud for a series of cons-- including bilking his father out of $53,000 -- that began in 1983, said Assistant U.S. Attorney Patrick Foley."I'd describe him as obviously a very bright, intelligent individual who chose to use his skills for illegal gain," Foley said. "It's actually a very unfortunate commentary on a kid who at the age of 20 decided to perpetrate a fraud on various individuals and made literally hundreds of thousands of dollars until he was caught."

Pandis is to be sentenced July 6 and could face up to 15 years in prison and %500,000 in fines.

The most lucrative of his scams involved borrowing rare, antique musical instruments, such as a 138-year-old Pierre Pacherelle violin made in France, from one dealer and selling them at bargain prices to another, Foley said.

"There is a common practice in the industry to lend rare instruments to people so they can try them out in their homes or their studios," the prosecutor said.

Pandis, posing as an investment counselor and lawyer, told the dealers that his clients wanted to buy their rare violins, violas and violin bows as investments but asked to inspect them first.

He never returned the instruments and made about $250,000 by selling them to other, unsuspecting dealers, Foley said.

Pandis was arrested Jan. 27 on a federal complaint and indicted Feb. 26.

He used the illicit profits for such things as a $32,000 Rolls Royce and trips to Paris, London, and Los Angeles, Foley said.

In December 1985, the indictment said, Pandis persuaded an elderly woman to close her personal money market account and let him manage about $100,000 of her money, Foley said.

Pandis spent most of the money on himself, the indictment contends.

He also is accused of stealing more than $40,000 from his father's individual retirement account and obtaining $13,000 in loans using his father's life insurance policy as collateral.