I appreciate the sensitivity of your situation; however, I must emphasize from an investor position what they are usually looking for. An investor is usually looking for a scenario that will make capital sense for their involvement. At $400,000, in this marketplace, your particular property isn't advantageous for an investor to want to get involved. This is in fact the hardest part of being a Realtor, is being the sound voice of reason that has to bring bad news.
My very first short sale was conducted on my parents home, into which they poured countless man hours, and it was tough sledding. But my family has sense moved on to bigger & better things, only to realize that what they had paled in comparison to what they COULD have. The first step in every journey is always the hardest, but it is necessary to reach your final destination.