I want to make sure I understand the nuances correctly before making this suggestion to to my better half, so hopefully BP can give me good advice about this and make sure I'm thinking through the repercussions correctly.TL;DR My wife hates living in the South and wants out ASAP and our owned primary residence doesn't come anywhere remotely close to cashflow potential, so how do we leave before the 2 year mark while also avoiding a hefty inflation-induced capital gains tax bill?

My wife and I house hacked a duplex for our very first home. We renovated the unit we lived in and have had tenants in the other side the entire time. Now we had a job change and have moved out of state so both sides ...

If it's your own primary residence you don't have to worry about capital gains tax.

Can I buy another property (thats intended to be a investment property) with loan on my name saying that will be my primary residence since I don't have any loan on my current house?

It will take some time to find a property that fits your buy box (price, rent to price ratio, etc).For primary property leases, you have a little leeway about when you move it. 

Does anyone know if you have to have a primary home to get a vacation home loan for an STR?

You may be thinking that’s a great deal in of itself (and it is) but the caveat to that is that it would be my primary residence for a year and then I would leave it to my parents to continue paying off.

The primary lessons learned were the value of a good contractor and staying on top of their work on a daily/weekly basis.

Mortgage on my primary goes from $2000 (PITI) to $2830.

I personally don't know if you can get assistance for multi-family- it just says "primary residence".