My REI pickle: VA loan residence limitation

[Rik Hunter]

Newbie investor, and my situation is likely atypical, this being about VA mortgages.

I bought a duplex several years ago (0 down at 3.75%; house-hacked) and refinanced at the started of Covid before I finished the rehab on both sides. We were living in one side and the other had just emptied. The rates were too low to pass up. I cashed out about $53k to pay off the rehab I had already done and to rehab the unit we were living in. 

At that same time, a single-family home down the street was sorta up for sale (I knew the owners from walking the dogs), off-market, and was below market value. I was able to purchase that on a second VA loan, bought points down with some of my refi money. Overall, it was great, but now that the duplex it done, I can't refinance it again with a VA because it's not my primary residence any longer (well, that's what the bank said). I know the value is likely up $25k-40k in my market.

Choices I see:

1. Leave loan alone and get an appraisal just so my insurance covers the greater value. 
2. Get a conventional loan and pay the 5% down? Navy Federal says it will only give me a 15 year, which takes my cash flow from $510/door to $245/door. I'd also have to have about $12k for the down payment for the new (high-end) appraised value (Not sure if I could use a check from a credit card, lol. I don't have the cash.). A 30 yr at their rates would lower my current mortgage because it's going from 3.0 to 2.125%. 
3. Or don't worry about refinancing the duplex but get a new appraisal for insurance purposes. 
4. And/or get the new duplex appraisal for insurance purposes and put that $12k that would be for a refi down payment into the SFH, which can easily be spent on putting in a half-bath (it's a 3-1) and other upgrades. Then, refinance it—fingers-crossed that the rates remain low over the next year.