I personally think they have to have some other source of income at this point. It could be something as simple as they own one (or several) of those vacation properties under some other LLC. I got an ad the other day for one of those highly themed rental houses in Orlando. It was $450,000, it was completely run and maintained by the property management company with an income of $85,000 after expenses. I'm sure there was a lot more to it, I didn't look past the ad, but it sounds like if you could pony up the $450, you'd be just bringing in money after 4-5 years. I can see them getting into some easy money scam like that.
I think they would take out business loans before they'd do a mortgage or HELOC. The house in their name, not the business...I would think that any debt taken on by them would be under the TTT name.