Yoon acquired the property at a sheriff's sale in 1996, after its previous owner - Faith Theological Seminary, where Yoon was once a chancellor - could not afford to pay back a $2.2 million loan.
His church has struggled ever since to keep up with the property taxes, which last year exceeded $135,000.
He took the issue to the U.S. Supreme Court, but his petition was denied in October.
Yoon said Wednesday he was sad to give up the estate. "But we don't have any choice," he said. "We've been fighting for 20 years."
His realtor, Frank Johnson of Berkshire Hathaway Fox & Roach, said that the listing had drawn several serious inquiries from around the country after only two days.
"I'm very impressed with the Internet," he said, noting that the listing has quickly spread from Zillow to Facebook, blogs, and news media. "I'm very happy with the reception."
And while some of the parties have expressed interest in redeveloping the site, Johnson said at least one person was looking to live in it.
"I had a call from somebody from Illinois, a very wealthy individual who has horses," Johnson said. "Of course, he would refurbish it. He must be very wealthy."
Trumbauer, the architect behind the Philadelphia Art Museum, designed Lynnewood Hall around 1900 for the family of industrialist Peter A.B. Widener.
In an interview last summer, Yoon said that what little money he had to invest in the property had gone toward maintaining the status quo. The grounds, once delicately manicured to rival a European villa's, have been filled in by dense woods and overgrown vines. The wrought-iron gates remain locked, and the Widener family's vast art collection is long gone.
Still, Johnson said, "it's a magnificent property.
"So hopefully we'll be able to accomplish our task as soon as possible."