Depending on the built in gain and how long you've lived there, you should be able to sell your current primary tax-free and roll any gains from that into your new primary residence, that is IRC section 121.Is there a set amount of time before you can move into the rental as your primary?

But if it’s money out of pocket for down payment (primary vs investment) there are definitely ways around that.

You may run into issues trying to take a HELOC out on an investment property, and even if you can I doubt you'd want to use it for a down payment for a primary because the rates are much higher.What kind of cash flow would you be generating from your multi once you move out?

Is that a HELOC on your primary or investment properties? 

I’m getting ready to apply to  HELOC on my primary.

However, my future plans with REI involve transitioning my primary income from nursing to REI.

They were snapped up quickly by primary home buyers, I would guess. 

The unfortunate thing here is that investment properties foreclose at a higher rate than primary homes so many banks just don't want the exposure to this.

Went to a community College for diploma, then worked, interned and got hired in her field of study before graduating college with a bachelor's last month with no debts in a growing field with high demand and six figure yearly salary.She bought a primary residence 2020 with 3% down and house hacked, which allowed her to live rent free for 2 years while tenants paid down the loan.

If things goes the way I anticipate, Austin will be probably my 3rd largest position in size but primary financial position.