The home hasn't been repaired yet. 

Assign certain tasks to one partner (i.e. accounting, repairs, showings, etc). 

Getting your RE license is a good way to gain knowledge but it teaches you how to assist buyers and sellers through the home buying/selling process.

They insisted this was just $8k worth of work and gave a $3k reduction in price stating they factored in $5k for repairs in the price already. 

I think it pays to have a good realtor that really knows the area to assist with this.

The roof in that area covers the room, and the back balcony/porch, and it is approximately 400 sq. feet.I got two estimates: 1) $4843.09 by Home Depot, the Sales Consultant stated that they need to repair my roof and the neighbor's together, they do not install new roofs on situations like mine, where the roof is "shared by two properties, due to potential liability issues being claimed by my neighbor.

The Seller also needs time to inspect, clean, and repair before returning the security deposits.

(I have a background in fire service, victims' assistance and have flipped a fire-damaged house).How many units?

I want to dive a little deeper and I think I will continue working on acquiring an investment property while, as you mentioned, networking to assist others in buying and selling. 

They all seem to be in decent repair (and i would obviously get inspections) but what is initially giving me pause is that they are all 80 to 100 years old. 100 year old houses are common in my area, but it begs the question, how old is to old?