Of course there are financing, closing costs, taxes, insurance and utilities during your hold period that reduce this to your 'net profit' something less Some would say 70% of ARV is a great deal.

This is mixed use as well as storage would be mixed use.. so check your zoning.. and insurance.. 

We have 750+ credit scores, decent liquidity for a down payment (we can put 25-30% down), we have modest but stable income, but we have tremendous student loan debt from law school and medical school.

In general states with income tax (CA) should avoid doing RE investing in states with high property tax even though I know of some San Diego RE investors that appear to have done very good investing in Texas (@Cody L.).Your cash flow on the Texas properties do not appear to have cap expense or vacancy factored in (and possibly not insurance or maintenance). 

There are still some things I am sort of "guessing", like the expenses (insurance, sewer, etc), but it's helping me learn where my gaps are in the analysis so that I know what I need to focus on.  

Have there been any insurance claims on the property?

The flat fee should be his insurance against you "wasting" his time, and if anything it should be refunded at closing, not charged.

The monthly cost breakdown is as follows:Mortgage - $1,200Taxes - $700Flood insurance - $170Home Insurance - $150Reserves - $500I went into this saying I wanted to pay no more than I currently am paying in rent ($900) to live in this place.  

Is the market stable or strong? 

You don't have to "work for a broker" but you do need a broker to hang your license with, train you (taking and passing the test does little to train you in the actual application of being a successful agent), and provide errors and omissions insurance.