I'm wondering if a HELOC is the only option to leverage my existing rentals to buy more?  

However, if the occupant is a tenant on an existing lease, you'll need to wait until the existing lease expires before you can move them out.  

That one that gets $695 you may get $550-600...Given some of the numbers you provided, you are looking at NOI of around $705 p/month before debt service...See if you can take the loan over subject-to existing financing..

., is your question really, should I leave the existing financing and take another loan once I've added value or should I retire the original financing when I take out I new loan?

Very rarely does it make more sense to bring in a mobile home instead of fix up the existing one.  

@@Abad MarroquinPre-foreclosures or "before the notice of sale deals" have to have equityI want to three months behind on payments, no moreAfter I pay back payments and fees I want at least 20% equity to take over the payments subject to (subject to existing financing)The ideal "subject to seller" is someone wants to protect their credit ratingThe Piti payments compared to market rent I want cash flow of at least a few hundred dollars a monthSo the deal discussed  I would not even consider

Use the loan that I just used to buy my first duplex in MN: Portfolio Conventional Loan, 3% Down Payment, No Mortgage Insurance (yes this loan really exists).

Or  can you do a subject to existing financing with 10% down of his equity position and have them hold a second for the balance.

We made the mistake of ripping every bit of the existing landscaping.

You really need to understand the value of the problem.In order to maintain low property taxes and avoid reassessment during the course of trust administration you'll need to obtain a "fiduciary mortgage" to the trust.If you take the property out of the trust, even temporarily to refinance, or to buy out the other beneficiaries, you'll trigger reassessment.Fiduciary mortgages will also limit you to borrow only about half the current value, less any existing liens and mortgages, if any.