I don't think procuring a new mortgage would be beneficial unless you need to pay off the cards.

My main dilemma is on financing my first investment property, as I do not have the funding to pay 20-25% down on a loan for investment.

two of my new tenants stopped paying rent.

Im willing to pay couple hundred bucks thats paying off my mortgage for a great tenant.

You'd need to evaluate risk as over leveraging can lead to disaster if your tenants stop paying.

Now it is a loan so this means you will have to pay it back when the loan is payed off or when you sell the property, but regardless it could my ticket into owning my first rental property.

Scenario 1: Pay off all mortgages and my net pre tax cash flow is about $120k/yr.

This take time and your demonstrated ability to pay on time, not so much the amount of volume you do.

Would it just be a double close to pay off the seller financing and I walk away with the appreciation and cash flow earned while under my control?

In other words, the deal should pencil whether you finance it or pay cash for it.