I am surprised by your comment on Bridge @Nathan Brooks is one of the most respected individuals in the industry.. maybe something fell through the cracks and he will want to know about it.

during refinance of 4th house, i asked banker if i could loan against the equity in house #4 to use as down payment for this house, #5. stopped #4 refinance and refinanced both at the same time. they were both refinancing and closing individually.

"House Hacking" is now such a fad that those MFH with one open unit fly off the market even faster than the shiny object dream homes for owner-occupiers these days. 

The rest focuses on the individual deal and if its numbers work.

What are some ways to secure financing for short -term Airbnb rentals knowing that they are more of a buy and hold.Any advice from individuals who have done this before on the best way to secure financing? 

All depends on the mood of the individual inspector that day. 

That's a seperate issue that's going to be handled eventually but the big issue is I suspect that an occupant in one of the units is dumping large objects next to and inside the dumpster (ie doors, mattresses, an elliptical....) that I then have to move out and pay to send to the dump.

Some individuals may not be familiar with the website or prefer to use a different method for various reasons (tech problems, how they set up accounts, income structures ect).

They often outperform individual investors if we exclude owner-occupied financing mechanisms which you wouldn't be able to use at scale with $4M anyways.TLDR:You can invest privately through real estate funds.

I specified single family because they are a dime a dozen, and in any MLS there should be good diamonds in the rough out there outside the mainstream of shiny objects being bid up above asking by desperate buyers (sometimes mispitched in listing to the wrong category by an idiot listing agent, which a good buyer agent can find and offer on as the only offer they've gotten in the past month!)