To be transparent, there is not 100% full proof way of preventing fraud.

Both properties have a substantial amount of equity that’s essentially sitting idle.Would it be a good idea to tap into this equity (through a HELOC, cash-out refinance, etc.) to fund future fix-and-flip projects or purchase additional rental properties?

We try to get ahead of the issue by preventing it in the first place.

Quote from @John Underwood: LOLI'm certain they will add restrictions to prevent people from doing this.

We routinely turn off boilers during the summer to prevent them from running to keep up to temp all the time during the warm months.

Also, for flips, I like to reserve an additional 15-20% in contingency for unforeseen conditions or changes. 

Here are some additional comments to add - please be sure to read the last comment regarding making contributions to both an IRA and 401k.Can I set up a SDIRA if I have full-time job?

Additionally, she stated she doesn’t want to pay either.

I know in residential lending you can get a HELOC to borrow a down payment to buy another property. Does this exist in the commercial realm? Current value of paid off property is roughly 350k , looking to borrow 75k-1...

But then we have to get into talking about the passive loss rules, which may prevent you from actually being able to claim a tax loss if the deduction is more than your rental or other passive income.Or you can claim the actual expenses (gas, insurance, etc) for the vehicle and regular depreciation, proportioned by the percent of business use of the vehicle.