We are interested in learning different successful real estate investing practices in Baltimore.

Best practice is to understand the law and act in a prudent manner.

Even if I don't end up saving money vs. the original offer, probably doesn't hurt to "practice" being aggressive in finding competitive financing...

As someone who practices law in disputes between contractors and homeowners in Nashville, it sounds like you are past the point of anyone being able to help you on a forum.

My wife and I have finally decided on Texas.  I have 2 requests.1. For our personal residence, we have identified areas that have good middle and high schools, which include Frisco, McKinney, Prosper, Plano, Providenc...

As for rehabilitating a partially vacant building, if possible you start with a vacant unit, rehab it, and either relocate an existing tenant or let it to a new tenant.  

This practice of renting by the room is very common in college towns; you can probably get some good ideas from the websites of these type of rentals, including rules, applications, & leases.  

Read all that you can, but also put what you are gaining into practice.

Do you plan to eventually relocate here?

A few practical things you can do in your situation to build your credit and start investing might be to get a CD secured loan at a credit union or bank.