I recommend snowballing when you have a 6 month emergency fund in place and can easy pay all of your monthly living expenses.   

In certain cities, it is very expensive for water service and some charge every month even if the usage is zero.

It's not too expensive to get started but it is expensive to maintain.

It's not that expensive.

The 50% rule is related to expenses, which does not include debt service, so your down payment won't affect that.If you're not planning to live in the property, you will have to put down at least 20-25%.

If you now the rents can support the principal, interest, taxes, and insurance and you can make enough to handle the expenses on the property I would go with a lender. 

Lately this person has become less reliable and more expensive.

Is 0.75 multiply against what is charged for rent for the month or is multiply to the cash flow I get after I subtract all expenses such as insurance, taxes, and paying the existing home mortgage?

After expenses, which included a special HOA assessment and a month's rent to my agent, 24 payments of $1595 ($38k) left ~$12k in rental profit.

Even if you do go ahead with the transfer (and I don't think $700 is too expensive by the way), I'd still go with the umbrella liability policy.