Question

Why did nixon say he sols his apartment in new york after he became president

Answer 1

I think it was so that he could stash the money away.

Answer 2

President Nixon was left in a great deal of debt following the Watergate scandal and the loss of his presidency.  Despite having secured publishing and consulting positions, Nixon was still in terrible financial straits.  He sold his apartment - rather dramatically - in order to support himself and his family.