What if the "repair" entails a tear off of the roof and full replacement?  

That being said I have a full time job and have a wife that is looking forward to painting and picking out fixtures and such when the kids go back to school in the next couple weeks.I had a GC give me an estimate on a potential property and the price came out to around $30k that includes roof, entire HVAC, bathroom, kitchen, flooring, drywall and paint.

Or a tree comes through the roof?  

However, the water/sewer in the city where our properties are only bills quarterly, so the tenant can rack up quite a bill by the time they're evicted.

I just put 5000 to be conservative but owner states he just put in new hot water heaters, roof is in good condition, the pics of the yard look like it is really well maintained, etc  The detached garage looks old but has a brand new roof on it and has been painted to match the apartment building. 

The bad: needs the rest of the electrical done, new roof/gutters, windows, sheetrock work and full kitchen rehab.

To figure out how much to put aside for capital expenses have an inspector tell you what's the useful life on big components.For example, if the inspector says the water heater has 5 years left of useful life and the roof still has 10 years.

We are lucky that mechanics and roof are in good condition, so a few less things to worry about.  

I had a new roof, gutters and soffits put on the house.  

I would plan on the lower end of rent values when calculating your #s.I could do 1% rent to price but it'd have to be in a stellar neighborhood with all new infrastructure (roof, AC, interior, etc) to drive down expected maintenance costs over the 15 years I can finance the property for.Don't get locked in with something that's a marginal performer with no exit strategy that doesn't result in a loss.