Also helps to have easy access to public transit and/or highway.

I'm just beginning the transition to larger multifamily, so any advice is helpful at the moment, and you seem very knowledgeable and proven in the space.

They are used as office/retail spaces.

All you can do is go in and inspect the place, but to what productive end if the previous owner still has access? 

Some people have shoddy credit, some people only focus on the 3.5% down payment (as opposed to the 3-5% down payment for conventional available right now), some people simply don't know and think FHA is the only way to go, some people do not have access to conventional financing for various reasons. 

I am looking to do the same thing as I have some vacant medical office space to fill up.

Even if you're planning on doing repairs, showings, leases, and all that jazz yourself, deployments are a thing and you'll want to have access to folks who can take care of things while you're away if they pop up. 

What does your lease say about running a business from the rented space?

It’s a crowded space but really there best thing when starting out.

Once you start buying more properties and become more successful the more valuable you will become to the agents and the more they will want to work with you.I know it sounds harsh but I as an agent am going to work with the client who I like and who is going to allow me to make the most money in the least amount of time.Also consider getting your real estate license again so you can at lest start doing the research easier and have full access to the MLS.