what other income sources do you have / how would you finance the new new property if your credit is bad? 

Zillow will show the source of the sold amount.

And as long as the sellers are using agents... that pretty much locks most buyers into using agents, too.I've said before that if there were ever a truly definitive tech source for appraising properties, that could be a game changer.

Thought I should crowd source this one.

But if I borrow from a specific source, my HELOC, only then I cannot deduct the interest?

Regarding your questions, in my opinion, you should look at your HELOC as one of many funding sources  & for every deal you should analyze which funding source (cash, your HELOC, refinancing one of your other multifamilies,....) is the most effective to use.

In sum, his main source of funding is to have the seller sign over their deed but maintain the financing in their name.

Doing your own sourcing rehab and renting is not the only way.

Additionally, if you are looking for some other good FB groups for military/veteran real estate investors, send me a message and I'll share the links(will get taken down if posted here), might get straight to the source of someone who's done this in Guam.

If I have a contract usually I'll try to target flippers in the area looking at various sources doing whatever I can to get in touch with them.