I've got a few resources for you.

If she continued to make changes without my prior written consent, then I would again serve her proper legal notices each time. 

The fact they are complaining online might be an indication the property manager dealt with them properly so be sure to ask the manager for their side of the story.I hope this basic guide helps.

I Don't trust and believe they would handle business properly from what I see.

We use a CPA for audits and tax returns but use either bookkeeper and in house resources for the daily/weekly tasks. 

I would say the school matters if you want to network a little and have the teacher as a resource but you already have the BP community.

If structured properly, between the assist and commission being the agent for myself, I would be paying the same or maybe even less to acquire the 300k property than I would the 100k property.

I want to get more doors, my goal is 20 units and I only have 4, my thoughts are that if I dump all money and resources of financing into one renovation and cosmetics...I will never buy more buildings and get to my goal.

A great resource i is the local BP meetup that usually happens the 3rd or 4th Tuesday of the month.

Operating expenses if run properly should be about 35% of gross rents on a small building like that giving you roughly a 9% cap rate.