There's actually a lot more to the whole equation, and it's been talked to death, but let me quickly illustrate a few more advantages to mortgage debt.- it's deductible on your taxes, provided you itemize (which every real estate investor should)- you're borrowing in today's dollars, but paying in future dollars; inflation over time for the USD tends to hover around 2% per year (Fed's goal, although at the moment it's slightly less), and mortgages right now are well below 4%, thus really meaning that you end up with only a <2% cost year on year, all else being equal- the cash you haven't spent on your property can go to other places, such as more real estate, the stock market (historical long-term yields of 7.5%), or giant billboards with you making a silly face on them (yield: priceless) All that being said, make sure you have a bit of a buffer and a few exit strategies.

You would need to get the property appraised as of the date of death.

When you wholesale and in general the key to being a great real estate investor is being able to find great deals and distressed properties is where to look: financial dirstress being in preforeclosure or underwater on their mortgage, personal distress death in family, loss of a job, or divorce, or poor property condition.

I have a son that is deathly allergic to animals.

So keep in mind that places like Saco, Kennebunk, and Bar Harbor tend to shut down during the winter as we all bundle up and try not to freeze to death for the 3 early months of the year, but during the summer time they are very attractive places to rent for short term rental, but there are other more creative opportunities to those who look outside the box.  

Death and taxes - they always come around knocking at some point.

@Jay HinrichsI am sorry to hear about the death of your project lead. 

Bumper to Bumper - Wall to Wall Traffic, even in the Toll Lane.

Do you think they will just quietly sit and starve to death? 

People forget about the human toll of financial downturns which many families struggle to recover from for years and years after the GDP readings say the recession is over.