At the end of the day if you are going to buy 10,20,50, 100, 500 or more tax sales a year, it is EXTREMELY counter productive and a waste of time to buy 2 or 5 or 10 or 20 from 15+ states.

Does anyone have any feedback or thoughts on which loan product to use? 

For me it started out being a RE broker and listing other developers product 50 years ago :) so you kind of grow into it..

We prettied her up, gave her a new sewer, new roof, new garage roof, cleared out a ton of junk, and put this into production in 2020.

Here's the link to get Sold, the first of the series https://store.biggerpockets.com/products/sold-every-real-est...

Even for Fannie/Freddie products, to qualify, the trust must be an Inter Vivos Revocable Trust.  

A HELOC can work for this, but keep in mind it has a variable rate, so it isn't the best product for keeping a balance long term. 

Again my advice comes from working with investors like "Rich Dad, Poor Dad" whose whole philosophy is if it cash flow dont sell it use the equity to buy another property. 

Speak to multiple lenders and see who can give you the most favorable terms and loan product.

We were about to close on a refi locking in a 2.5% 30 year fixed and pulled the plug at the last minute to switch to the All in One, but the lender pretty much told me why I was making a poor choice, so this is very affirming.