For instance, there could be a great chance for an amenable loan modification or a deed in lieu that could occur even in a long foreclosure state that would alleviate the inherent risk of a long, drawn out foreclosure.

Mail mishaps occur and so do on-line mishaps and bank handling mishaps.

If your agent is throwing away 75% of the properties before you even get to see them, you are at a severe disadvantage.I also think you are way over-estimating the number of pocket deals that occur in any given market. 

Or, are you counting on the steady appreciation that has occurred during the last 3 years to continue over the next three?

That's a persuasion technique called "thinking past the sale"  Get the other party to think about what things will be like after the sale and it mentally moves them to a place where the sale has already occurred thereby making it an easier decision to accept the sale. 

Upside-down deals typically end up in foreclosure or short-sale... or the owner simply keeps paying the mortgages.They are bad candidates for investors because there is no equity to work with.Until a foreclosure occurs and junior liens are wiped out, there is really nothing to work for.

If the numbers work going into the deal, I would leave the guy in place, but let him know a modest increase will occur at next lease renewal.

If that's the case then the fact that they happened to find a new property already is a happy accident. 

This will keep the parents on the kids a bit (but damages will occure)4.) 

Since I have multiple properties with individual accounts this makes it covenant to cover any unplanned expenses as they occur.