If you are worried about this there are companies that handle servicing these payments automatically on a scheduling system if you have a bunch of them. 

I work in IT at a local boat manufacture and my wife works in the office of a flooring company in Longview.  

From what I can tell, the only thing saving these companies is that they have great marketing and do a good job raising money from new investors for the next project while polishing the turd of their last project so they can sell themselves as a great success story.

real estate training has always been a big money bizz.. its really promulgated though with U tube and how easy it is to throw you stuff out there.. but to really get wealthy doing it you do need a ton of dough for marketing or a great relationship with a fullfilment company.

There are companies that can do handwritten letters for you.

And it can be done there locally.When I was active in Jackson there was my company and another called SIF one of the owners was married to a local doctor if I recall. 

Is it high interest rates, finding reliable lenders, or something else entirely?

The company gets more and more greedier over the time.

The property is gated so many rent out all 12 bedrooms and bathrooms for parties, retreats, anniversaries, team meetings and special celebrations.It's private and perfect for those who want privacy when they need it and company when they want it.It has appreciated and is now worth at least 3 million and we are looking for funding to refinance and share the profits with our investors.

I have seen this work in high priced markets like San Jose Ca.. where the property owner is a very wealthy business person with no time for rentals and the person they sublet to is close t them either friend or bizz associate and will work the property to make  the delta as the owner just does not want to mess with day to day and there is extreme trust.The other thing I have done personally is with the insurance companies ..