My dilemma is whether I use my VA loan for the multi family which will turn into an investment property after I change duty stations in two years or save that VA loan for my personal residence once I establish more permanent roots upon competition of my service. 

I changed the locks and took possession myself on the grounds that it was vacant and therefore the prior owner was not in possession.

Are you going to change locks or rotate codes to after someone stays?

Negotiate a lower price if inspections warrant that, do a walk through the day of signing, and if everything is still okay--no squatters etc-- go sign the papers, pay the money, get the keys, change the locks and move in...I would guess I might have missed a step or two...

I have told the lady about it several times, and she says she will tell her sister, and nothing changes. 

I think you'll find your goals may change once you jump into real estate.

I've used the house flipping calculator here on bigger pockets, although I'm thinking the nubmers would change a little big given the fact that it would be my primary residence for a minimun of 2 years.

Having your first child is a big change and is time demanding, so is your first rental property! 

I am subject to interest rate changes and call risk. 

It changes the seller's mindset from a yes/no to choices.