We're talking new roofs, new interior layouts, bathrooms, kitchens, everything. 

The roof, appliances, driveway, etc. will need to be replaced in time, and the CapEx is used to estimate those long-term replacement costs.  

What if it needs a new roof but inside if mostly ok?

I assume it's just the bigger stuff and single family homes (electrical, roofing, etc) but just want to make sure as I want everything done the right way (not always common here in Miami.)

How old is the home- are you incorporating longer term rehabs- like roof, plumbing, windows, electrical and Heating/ & AC?  

Check on the foundation, roof, plumbing, and electrical.

Replace a roof and you will most-likely have zero profit for the year in actual dollars.  

Since closing on our current residence we have basically updated everything (outside: deck, roof, paint, inside: paint, bathrooms, appliances, flooring, etc).

Is the roof fairly old or is some ther big ticket item going out soon?

So definitely take note of the "big 4" while you are looking at the property (Roof, A/C *indoor and outdoor*, Plumbing, Electrical), plus anything else you can see.