My appraiser was very open for me to provide "support" for the value and so I got no pushback.

Also, I had no credit score here in the US, so it was difficult to get a loan.

I have a job offer that will make slightly more than I currently make and will provide housing for my family so no expenses there.

Of course the bank says "no problem", I start the process etc, then after credit pull and everything state "thing's have changed and you cannot own more than 3 investment properties" so now I'm at a standstill and they want to push me to commercial side, which in this case is requiring them to take my first and have to refi the balance and lose my rate and then tap a HELOC afterwards at commercial terms.

There's no good strategy without an objective. 

You will have representation and your offer will be specific with no room for assumptions, etc.

The odds of that an engineer will say its perfectly up to code and it requires no changes is probably pretty low. 

Gulf shores no prob.

In those 2 states I might just say “No, I’d prefer to keep using my garage.”

I also have an investment strategy in place (core/core+ investments, minimal to no rehab, aiming for 8%-12% IRR over a long holding period).