No distressed businesses and none with insufficient sale price. 

For real estate entrepreneurs, like us, it is ok to be insufficient on one part of our business.

Your lease should specifically address-one time with insufficient funds for rent checks means they can never again pay by personal check.

These are the polar opposites of minimally-funded life insurance policies: they type that 99% of people buy when they buy a permanent life insurance policy.Only minimally-funded policies run the risk of lapsing from insufficient cash value to cover the rising cost of mortality.

Once you have this all in place, do a market survey to find out which market has the inventory in sufficient quantity, what they cost on average and the potential for 2-4%+ annual rental increases for making all this work in a reasonable time frame (5-7 years) and start working your plan. 

For your first couple of deals, you'll probably want to look for places that just need some cosmetic repair (paint, flooring, etc.) and make sure you steer clear of any structural issues like foundation insufficiencies.

But as a Nutritional Therapist, you peaked my interest with the word 'diabetes' in your post.

Overestimating response rates and doing insufficient marketing to generate enough leads2.

I'm not sure about the actual extent or likely duration of this, but it's happening at least to some extent right now.It's not hard to come by anecdotal evidence in the form of people talking about bidding wars, insufficient inventory, etc.As an example from my own personal experience, I listed one of my rentals that had gone vacant.

I guess the letter of administration was insufficient.