Manteca’s highest profile home — the opulent 30,000-square-foot mansion built by grape broker Michael Hat — could become a high priced teardown. Richland Communities, which owns the mansion and surrounding vineyards just south of Woodward Avenue, is covering its bets on future housing demand in Manteca. They have been working with the city to possibly annex the 184-acre site that borders Sedan Avenue on the south and east, plus the Woodward Park neighborhoods near where Pillsbury Avenue dead-ends to the north to develop the site as an age-restricted community similar to Del Webb at Woodbridge.