is 1/3 materials, 1/3 labor, 1/3 profit still what most GCs expect?

[Corbett Brasington]

I am asking this question for two reasons:

1.  Is this what a healthy project looks like to a GC?  Markup recommendations are all over the place from 20% to 67% and I don't know what is reasonable.  I don't want to deal with contractors that need me to float their working capital with large deposits.  I want contractors who have enough markup and a proper payment schedule to reduce the upfront load to me (allows me to scale more).  

2.  Finding reliable "how to estimate repair costs" has been a roller coaster with how much the cost of things have changed.  I have no heard that cosmetic rehabs are $30ppsf and full guts are $60ppsf and new builds are $125ppsf, I don't know what to trust.  I want to create my own templates for scope of work with real numbers from a big box store.  If the 1/3, 1/3, 1/3 is reasonable I can take the entire cost of materials for the whole house and back into the cost of hiring a GC.