We will use primarily as a vacation home for ourselves, but may at times rent it out (via airbnb, vrbo, etc). 

I have used the approach mentioned by @Kyle J. via Mr Landlord.

Anything wrong with seller financing then getting refinancing via conventional lending asap?

Purchase price: $475,000 Cash invested: $70,000 4 Unit acquired with business partner Chris via Hard money.

I am looking to ultimately create supplemental income via cash flow from rental properties.

So, I reside in San Diego, what I did was to leverage my primary residence via a Cash Out Refi to purchase a distressed property here in San Diego.

I would think there would be risks, I think they get around any licensing based on not having to do trust accounting (funds are still deposited directly to the owner who then pays the co-host via Venmo or whatever).Your experience far outweighs mine I am sure! 

You can pay yourself via payrollYou don't need to meet a time threshold, the IRS will treat the entity as the actor and as long as the activities of the entity are consistent with the business you will be fine.I am an investor & operate a property management business; I have it set up the way I describe here & I have not had any issues.

With the built-up equity in your current portfolio, I'd recommend cross-collateralization via your purchase loan. 

Can somebody explain the different between subject to via the seller and seller financing?