For comparison, a Navy Federal FCU personal loan will be in the 15s%

We closed on the construction loan June of 2021, the permit came through Nov of 2021.

The SST doesn't apply for legal 2-flats so if you want to use FHA it's probably better to target those that maybe also have a non-conforming basement or attic unit.This is why the 5% down conventional loan is a game changer for house hackers.

I recommend that you find a trusted or recommended Mortgage Loan Originator (MLO), who can give you options for property-based loans (mostly investment loans) and they don't use your taxes but the P&L of the property.

Purchase price: $240,000 Cash invested: $60,000 purchased this distressed duplex using owner financing for $240K and a $60K hard money loan for renovations.

I think you would be wise to sell and use the VA loan for your new home. 

The deal will leave the seller at your sons mercy for decades (the life of the loan).

Get it under agreement for less than asking price and offer to bring the loan current and have them carry that loan.The way I see it is they are just getting MLS properties under agreement - the last five I looked at had been sitting on the market for more than 150 days (overpriced) because the payoff of the loan would not be satisfied at lower price point. 

So for the first property which will cost over $1 mil to construct, there will be stacked loans, essentially $280K will come from loan assistance program,( the name is not correct but the same idea).

Hard money and private investing are both ways to finance flips, but they work a little differently.Hard money loans are typically from companies or private lenders that specialize in short-term, high-interest loans.