Access, jobs, and drugs are your main challenges.

Seller: No, he died of a drug overdose two months ago.Me: Oh, geez.

@Wayne Brooks My Rays are prescription and I can't grow hair anymore except places it shouldn't grow.

Do you think that the judge is going to believe that I was not selling drugs?

Same thing happens here ... the taxman deems that interest was charged at their prescriptive rate ... and they collect their share. 

While I agree it is certainly a job, it remains the exact definition of investing.I won't bother commenting on the rest, if I wanted to waste brain cells, I would become a drug attic.

Are there noisy neighbors a bully on the block or drug dealers hanging out on the corner...?

Here are the big six (6) reasons people leave behind a vacant property: 1) "Skipped" on bills or other people 2) Drugs and alcohol 3) Incarceration 4) Severe mental & emotional problems 5) Senility 6) Death By reverse engineering each vacant property opportunity, talking to neighbors and others in the immediate community, you ought to be able to get a lead on which of the above scenario is most likely.

That bathroom reminds me of the "don't do drugs" commercials from the 80's where the skinny heroin addict was laying on the filthy bathroom floor.

You have a felony record, keep on walking, you have an eviction, there's the door, any drug history, you don't know me.