After all managing vacation rental is like having another job, the ultimate goal for every investor should be to create enough "passive" income without having to work to earn it.

My only option to for making more profit (other than reducing the all-in cost as a percentage of ARV) is more favorable terms with the private lender (i.e. 8% return). 

Congrats on your well earned success here, and I look forward to hearing more about what you have going on soon! 

You must be a licensed agent or broker to earn commissions.

Well you better get the heloc while you still have the equity and use it carefully otherwise in the downturn when they want their money back they’ll freeze or reduce your line. 

A "good Samaritan" maintenance person may have done it to reduce energy consumption and didn't realize the tenants would be so severely affected.

You would more than likely need to sell the property yourself because $40,000 in profit will be reduced by commissions and closing costs.Option. 

If I receive a small cash flow of $600+/month, that is nice, but mainly I want to do it for tax deductions against my personal income so that I ultimately pay less in taxes and earn more throughout the year.Assuming I have a single member LLC with the property under said LLC, when I go to do my taxes - TurboTax asks me "Let's See if You're a Real Estate Professional"So of course I have a few questions:1. 

Here are a few options:1)HELOC for repairs and flip it for profit2)HELOC for more rentals and hold current to pay off HELOC3)Seller finance to reduce tax obligation and receive. a large enough initial downpayment from buyer to use FHA for a primary4) Hold and use cashflow with the specific intent to invest all residual income5) Sell and take "Capital Gains" hit but purchase another property to help offset it6) Transfer deed to an LLC to remove it from Grandma's name (this opens another door of possibilities but may trigger tax increase due to transfer of ownership)I can go on, and others with different approaches can add to this list as well.

You can separate it with an exterior door if you want to reduce noise coming in but usually you wouldn't be allowed to put a lock on the door from the upper level (locking them downstairs).