And, to be honest, I think there's benefit to being at arms-length with tenants. 

Is there a world where there are any benefits?

If you go to an experienced HML there will be an educational benefit to speaking to them about the property that could be better to have happened before you negotiate the contract.

Not only are you going to get 2 mortgages paid off you will also benefit from appreciation on 2 properties instead of 1.

For a more passive approach but still with potential tax benefits of long term ownership I would probably invest in an outstanding sponsor's syndication or NNN commercial leases.However, if the only capital I had was borrowed from my home, I would address that issue. 

After my last trip I have to admit the concerns outweigh the benefits and I am going to sell the boat up here and use the money as down payment on another rental.  

You may have some liability protection for assets not held in the LLC and check with an accountant for any possible benefits from the new tax law.

That is the primary benefit of a LLC 99.9% of the time ........  

@Upen Patel :  So, if I am reading into this correctly, there is no real benefit to being a co-borrower as opposed to a guarantor on the LLC loan. 

If there is a pressing situation that requires you to sell to get the cash in your lifetime then it is doubtful that you will squawk at having to pay tax at that time.But if your tax is in the $120K range and you get to invest that for a net return including of depreciation benefit for say 8% then after 10 years you will have more than doubled that tax in return and compounded interest.