Have had an Airbnb out of our primary residence basement for 2.5 years and bought a duplex in November after taking out a HELOC on our primary to use for the down payment and some renovations. 

In Charleston, I believe the rule is that you have to live on the property as your primary residence unless the property is in an STR overlay district.I personally know some investors who are starting to struggle a little with occupancy/bookings.

First of all take the primary residence exemption of $500K out of the equation. 

If you are planning to make it your primary business -  you will need to really hustle, have meaningful reserve funds and/or a strong sphere of influence to get the time, money and resources you so desire.Can you be an investor and work 60 hours a week?

Purchase price: $672,000 I bought a primary home with a 5.1% rate.

So if you own an STNL asset at 15 years primary and want to sell at 12 years primary remaining there is still a ton of demand.

The primary lender sold the promissory note but kept the mortgage.

I think you would be far better served by just getting a separate bank account to run your business if that's your primary intent on using LLC.

You will likely find that some banks are much more favorable to lending to primary homeowners, while some may lean towards investors. 

@Jefferson Black- thanks ..based on the post I am not sure if the MH is your primary home or an investmenet property ??