He said it is "nearly impossible" to get a good interest rate by purchasing through an LLC and that it will take an "arm and a leg" to get the deal closed.

I would assume if you were planning to do an interest rate reduction refinance you would do all of them at the same time. 

With current rates my mortgage would be about 4600$ and doing basic math i would have to pay about 1300$ to live in one unit.

I am looking for the best options to get a long term rate around 7%. 

I have roughly 50-70% equity in each property, each property has a 30/yr mortgage with interest rates that are pretty low (3-4%).

I have heard there are smaller lending groups where you can purchase a note of the loan for a private investor with fairly good return rates.

I'm looking into a few different options now: HELOC on other investment properties (though I'm finding rates are 11%-13%), a business loan on another business I own, and negotiating with vendors to take deferred payments. 

IMO this makes Texas the preferred choice for series LLC, although the (over rated) non publishing of organizational information in Wyoming and Nevada will have others disagree.  

This is EXACLTY what Clayton Morris did to his clients dumped them into low end properties and millions were lost.. this is something in my personal opinion that will never work and investors are going to sign on to these high interest rate private mortgages and find themselves in trouble. thing of it logically if you have the cheapest homes basically in the entire US what kind of renters are they going to attract..  

If they don't like it, you can find another tenant willing to pay market rate and pet fees.