I applaud you for not wanting to be dishonest or mislead your potential seller, because that is exactly what most "wholesalers" would do, and (in many investors minds) seems to make up the majority of the business. 

One person says "You owe $X and I owe $Y" basing the calculation on a dishonest accounting of the bill.

As with any industry, there are a lot of dishonest people in it... always get multiple quotes. 

He asked me if I'd rent to them again and I said I never actually rented to them in the first place, and even though they didn't cause any problems and paid the rent on time, no I wouldn't rent to them because I know them to be dishonest and were unwilling to sign a contract. 

Honest people don't suddenly become dishonest because they experience some misfortune.

If you want to retire from your full time job and become a RE investor... you can expect long hours, messy jobs, dealing with unhappy clients, lawsuits, dealing with dishonest vendors, creating business systems, accounting systems, tenant law, and a plethora of other issues that will equate to a full time job with unpaid OT

Was reading this eye opening thread here....https://www.biggerpockets.com/forums/223/topics/39...and one common occurrence for this guy was finding many dishonest buyers and sellers. 

When I meet brokers or owners that hand me their pro-forma numbers and they don't include property management, I immediately think that they are either: (1) dishonest; (2) careless; or (3) plain stupid. 

I personally think anyone recommending it either got very lucky or is dishonest.

He's a very smart person but I found it intellectually dishonest to ignore all the landlords that have become millionaires through D-Class properties. why not explain the positives in negatives and let individuals make up their own minds or learn through their own experience?