守株待兔也是一法哈。
你会说,我不要10-20% down, so I should sell to him for more. Fair enough. But 20-30% higher price AND significantly higher rate? Only people without much brain will take this deal. Because he/she in fact took such deal, I would not expect him/her to be smart enough to keep his/her right for refin and actually come to you to refi today.
Imagine if you sell to him/her for $350k and the interest rate is 6%, what would be you return? Forget about the risk that you are intaking.