Pay it off with a commercial DSCR refinance loan once you've gotten the rents up to an amount that will allow you to cash out on your HELOC.I like using my HELOC but only in short-term scenarios because it's a floating rate and I can't control when or how the bank will make adjustments to the payback variables. 

Because I don't control the process.

Also you may want to consider Checkbook IRA (aka IRA owned LLC), which will enable you to bypass the custodian and have checkbook control over your retirement funds.

I wouldn't look at fix and flip for 100+ year old properties I'd recommend urban infill new construction much more control less stressful more advanced more value easier exit, etc etc 

Either way, I recommend finding peace with what you can't control (whether that is eviction or them living in the mobile home); otherwise, you let the siblings keep winning if they impact your happiness.

The way I see it is that the monthly fee should cover coordinating routine maintenance (HVAC tuneup or minor maintenance, leaky faucets and drains, sprinklers, minor pest control, etc.), but larger ticket items that may require multiple bids, permits, or otherwise could have reasonably been prevented should be handled separately and charged to the owner.

i iknow of a couple investors who are members of those sites. i thought about it, but didn't when they couldn't tell me how many leads came in per month on avg.i like being in control of my own marketing and once u have it going consistently the phone will ring. the other leads are icing on the cake

One bad investment can ruin most or all of a diversified portfolio and you have no control over how things will go.  

To summarize, your JADU should not be rent controlled due to 15 year exemption.  

So, in sum, house hacking can be when you are able leverage low down payments in order to control an asset (use an FHA loan and rent out the other rooms/units, use the VA loan with no down payment to ultimately turn the property into a rental property, etc.).