I suggest you determine what the value of the opportunity is before determining Jim much you can afford to budget finding the owner.I use the following acronym: PETIOPROPERTYEQUITYTITLEINTERESTSOPPORTUNITYWith this format I can determine where the sweet spot is in the situation.Since you are hopefully chasing a bunch of equity, you might be able to budget $50-100 or even more to skip trace a missing owner, if alive. 

It could be mom or dad or a girl friend or a drinking buddy.

Good thing, because the attorney had dropped the ball and was about to miss a deadline for the bankruptcy hearing - I spent 3 days going through evertying I could find on Bankruptcy - I went to court, filed pro-se (for myself) against the attorney for the people that were trying to stop me from foreclosing...We won!

Is there some secret magic I am missing or have yet to learn?

I really miss that now that we are in intentional holding pattern for awhile.  

Individual doors can be replicated/replaced if missing by a good cabinet shop.Contact the city engineer about the flooding issue.  

I was looking for ideas and trying to make sure I wasn't missing some other type of mortgage loan others have used in my situation. 

Anything else I'm missing?

I'm no expert but I would guess not much.Every disclosure I ever filled out said, " to the best of your knowledge" and every inspectors report I ever saw said at the bottom, something to the effect that if they miss something you can not hold them liable.

@Raj Kumar, Alsip is kind of hit or miss.