But during the buyer’s due diligence, several unexpected issues surfaced, each cutting deeper into the profit I had worked years to earn.The first issue was with the water lines.

And while that number varies somewhat, the most common number of different issues that minimizes risk is 21.  

@Ryan BroschardHi Ryan,You have hit a common issue many new investors fail to anticipate.  

Also know that building a home seldom goes as expected - I have relatives that just built a nicer house… they thought it would take 9 months… it literally took 18-24 months between delays in permitting and the builder just not being able to get it done in a timely manner - often due to sub-contractor issues.  

I even try to unsell them on the business by sharing my financial losses, litigation,  market shifts, permit purgatory, shady contractors,  clouded title issues,  paranormal activity, squatters, mold, etc.

We never fixed the issues, we didn't.

You can sell a property with tenants with no issues the only thing is you wont see as good of a price for the property since it will likely be an investor purchasing it.

One thing to consider on the credit card option is that a lot of contractors don’t accept them so that could be an issue.

The issue I have with Zillow specifically is that every URL to an address contains an unique identifier called a ZPID.

Since the properties are in New York you have a few extra steps you need to do to keep all of your funds out of NYs hands at closing.Here's an interesting BP thread on the South Carolina property tax issue you mentioned. https://www.biggerpockets.com/forums/725/topics/604427-south....