That Jill Zarin, formerly of “The Real Housewives of New York City,” will host her third annual luxury luncheon in Southampton with a portion of the proceeds to benefit The Eric Trump Foundation and the Samuel Waxman Cancer Research Foundation this Saturday — the same day that Corcoran broker Gary DePersia and RAND Luxury host a brunch at 948 Deerfield Rd. in Water Mill, now on the market for $6.49 million.