So by selling out for a mere $700,000--if he really did--Brown revealed his expectation that competitors (presumably other high-ranking officials with the means to influence trade policy) were prepared to undercut him.
Brown sold for $700,000, but would have sold for much less.
mnli hypothesis: Brown sold for $700,000, but would have sold for much less. premise: So by selling out for a mere $700,000--if he really did--Brown revealed his expectation that competitors (presumably other high-ranking officials with the means to influence trade policy) were prepared to undercut him.