As part of the trial payment plan the borrower was able to put down $3,000 towards arrearages and agreed to an increased monthly payments.Borrower has made 6 months of consistent payments and we modified the loan to have the past due rolled into the unpaid principal balance.

Well because the popular people tell you that if it doesn't work, you need to do more because you need to stay consistent.

In other STR owners I have spoke with, this is consistently the one overhead they find most challenging to cover given $100+ average cost. 

,Like you I've gotten into the mindset of modular homes and I am working on the development of a Duplex community consisting of 5 duplexes on 1 acre.

Building positive relationships with tenants can increase their retention and reduce turnover, promoting consistent rental income.Consider FHA loans with lower down payment requirements if you're starting with limited capital.

The core 4 consists of a realtor, contractor, property manager, and a lender.

From there be consistent and make it a daily habit to do these tasks 

However, if you're looking for payment reliability, I'd recommend a slightly different strategy that aligns well with consistent income.Partnering with non-profit organizations that support vulnerable populations, like the Veterans Affairs or groups assisting people with developmental disabilities, could be highly beneficial.

The nicer area's you're giving up some cash flow for the consistency of the clientele and in my experience I've seen those areas appreciate better over time as well. 

I found that as well, (first search result iirc) but it turns out to be one guy trying to recruit mentees  as opposed to a group of independent investors like I understood a normal REIA to consist of which is more what I’d be looking for.