One other downside besides the higher rate and lack of a 30yr. fixed option is that having multiple properties in one loan can complicate the sale of the properties individually, or to refinance, pull cash out, pull a line of credit, etc.Other options you might consider:1031 exchange those SFR's for a Multifamily building(s) (This is what I would do).Pay down the smallest mortgage to free up a new mortgage.Use a HELOC.

Pay the deposit back to the individual that gave it to you.

Working with more experienced individuals will help you learn and make less mistakes.So, I’d say go for it!

I've heard of single LLC, series LLC, LLC with individual land or revokable trusts for each property within an LLC & even an LLC for each property. 

I'd love to meet with someone in the area, preferably an individual who knows the business and owns property so that I can gain better insight towards real estate.

Your liability policy will be the individual policy on the property. 

I’m looking to buy a 2-3 flat in Chicago and was wondering if anyone has had any experience buying a multi unit, living in one bedroom and renting out the other bedrooms in the units individually and not as a whole. 

Not sure if they are platting the lots for individual resale.

One resource Texans have is the Texas A&M University Real Estate Center which provides a lot of good data for most MSAs and individual cities.

This is the combined net worth of the partners, not each individual.