Next I recommend finding a realtor for MFR searching.If you want to find  mixed use building and run your business in the same establishment that can work pending on your goals.  

I would start doing a lot of research to get yourself educated, you really can't do anything until you establish a good foundation to build off of.

After that, if you want to do a few small things for her, that you don't have to do, to establish goodwill, then fine.

I established one for some larger multi's for anonymity and liability reasons only.  

Labor, your labor can establish sweat equity, you may quickly force appreciation to increase value.

Be sure to establish your minimum criteria to rent, place a decent ad that gives enough information so people can self eliminate themselves if they are unlikely to meet your criteria, prepare yourself for the onslaught of inquiries, ask good questions before taking the time to show the properties. 

If the previous owner had a code violation with any utility company it would be apparent when trying to re-establish that utility.

Paint can be kind of a tricky one since wear and tear vs damage is a little more difficult to establish, it's not like having a burn mark or permanent stain in carpet.

It is unfortunate that a man established a business over 30 years then dealt with customers so poorly.

First, treating the LLC properly in its establishment and operation.