The balance of his home mortgage is  $550k with 6.5% APR.

This leaves a smaller balance disputed but if you do not pay them anything until its resolved, it could lead to issues if it goes to court.3.

If you have the cash to complete the transaction as is, I would recommend simply paying the balance.  

It's work to get these two to balance out - if working with small sums, I don't think it's worth it and I'd rather invest it more passively. 

We calculate rent plus all debt payments as a percentage of gross monthly income.Our underwriters strive to analyze and balance all the information above to determine the statistical likelihood of a tenant paying their rent on time.ApprovalOnce an applicant is approved, we require a nonrefundable Holding Fee to make sure they are serious and don’t change their minds.

I do however, have full availability on my HELOC, various credit cards that are offering me 0% balance transfer checks for up to 12 months, and various retirement funds (Roth IRA, traditional 401k, etc.)I'm already a homeowner in SoCal, but I want to buy my first LTR SFR someplace like Cleveland since the price point is attractive.

How does it save me money if I keep increasing the balance of the loan product.See how they answer those questions.

It’s all about finding that balance and experimenting with what works best in your market!

On the other hand, a good passive investor hires sponsors who have years more experience than they can ever hope to achieve.So again, this is why I feel a balanced portfolio needs to have both types. 

Umbrella Insurance: Adds protection for high-cost liability claims but doesn’t fully separate assets as LLCs do.RecommendationConsider one LLC per city for balanced liability protection and simpler management, paired with umbrella insurance for added coverage.