In 1996, Biden sold a home in Greenville for the asking price of $1.2 million — more than six times what he paid two decades earlier — to John R. Cochran III, a top executive at the MBNA credit card bank that was a longtime political benefactor. Using profits from that sale, Biden paid $350,000 cash to real estate executive and developer Keith D. Stoltz for 4.2 vacant acres — a long, narrow lot a few miles from Biden’s old home. Stoltz had bought that same lot five years earlier for the same price. Stephen Pyle, who sold the land to Stoltz in 1991, said he was surprised that Stoltz, who lived on a neighboring estate, did not make any profit selling to Biden. “That doesn’t sound like Keith Stoltz,” Pyle, an artist who now lives in Texas, said of Stoltz, whose company recently proposed a $525 million project at nearby Barley Mill Plaza, a former DuPont Co. office campus.