Are there any "for dummies" style guides to even the most basic of guides?

Basically there were two owners that bought/built the whole street of duplexes in the 70's.

Work is pretty basic, mostly wall repair and paint, some hardwood refinishing, installation of new toilet, and vanity, refinishing of a tub and removal of vines from the stucco on the outside of the home.

While I have been working with a few local investors, I am always open to share in new deals and new projects with like minded people. 

Flipping California properties 200-500 acquisition price points with normalized net returns of 15% has allowed us to capture between 30k-75K per project average to around 52.5K per project.

The PM can make or break you--being remote, you will basically be at their mercy to deal with problematic tenants, find tenants and keep vacancy low, collect your money, find contractors... in short, every aspect of actually running the business. 

The value add will be mostly in increasing the projects occupancy from low 70s% to market occupancy (about 94% physical, 91-92% economic).

I feel my biggest weaknesses from not being "in the game" are estimating rents/expenses for my projections.

Recently a few friends have suggested that I invest some money into the basics such as new plumbing and some cosmetic work so that I can at least market it for a higher price, however, I am hesitant to do this as I am not sure if anyone will buy once the updates are completed.

I project that with the changes that I'd make, I may be able to lease the condo (3 bedroom, 3.5 bath, ~2000sf) at $225/night.