Joel Cantor, developer of St. Petersburg's Signature Place condo tower, has juggled a handful of lawsuits from disgruntled buyers. But the most recent unhappy purchaser was a doozy: His own father, Irwin Cantor. The elder Cantor sued his son's company in late August, demanding to downsize from a $3.26 million penthouse to something more affordable. Joel Cantor said his father was working an "angle" so that Fifth Third Bank, the tower's main financier, would agree to the contract change. In fact, the younger Cantor said he threw his weight behind his father's request, and both sides recently settled. Cantor senior will close this month on a humbler 2-bedroom unit in the tower at First Avenue S. and Second Street. "He wasn't mad at me," Joel Cantor said. "He was just trying to get the bank to respond." The 36-story building has completed sales on about 65 of its 220 units.