HELOCs are usually variable rate and there may be yearly fees associated with maintaining the HELOC.

But usually section 8 is the same or slightly above market rents.

Most sellers only care if you close so you can usually use another form of capital stack other than what is on the agreement, however, the seller can force you to use the originally agreed-upon payment method. 

Prepayment penalties- usually 1-5 year terms.

The one guy I spoke with said they make money only when they sell to potential investors and they only sell new construction homes that are usually pre-leased to buyers (currently they are building in Texas state and Missouri State).

., and usually 8am-12/1pm daily. 

That's usually how it goes with lenders that struggle with spelling. 

Coming from a family of lawyers the ones in my experience that make less than that are usually just not that motivated or are not that good at what they do.  

HELOC is usually a good option for something short term, you, don't really want to buy a long term rental property on a HELOC.

I also want to say that if you see this as a true passive investment, you'll be in for a surprise because it's anything but....usually.