Example: he runs through a basic example of a 2k sqft house - more specifically, covering the 1) Kitchen 2) Bathrooms 3) Windows 4) Roof 5) Flooring 6) Trim/Doors and 7) Landscaping and he includes not only the cost of the individual materials, but labor spreads as well.

Depending on your end game- rental -flip - hold, for rentals- I get 12x12 granite tiles (under 5 bucks each) butt them together and trim it with 2" wood that matches either the granite or the cabinets.

Others do some framing but forget about the drywall which leaves some obnoxious sized trim on the interior.  

We also did an interior build out (framing, insulation, drywall, electric, trim, paint, and epoxy flooring), along with a walk-door, plumbing (toilet and shower installed, and rough plumbing for bathroom and kitchen sink), and 5 windows.

Sometimes I provide materials (tile and grout for tile jobs, shower valves/trim, vanities for plumbing jobs, etc) but that isn't necessarily to save money, it is to save time, so the items are chosen and ready for the contractor to install.

By proper installation of quality tracks/rods, you don't have tenants damaging trim and walls putting up (or reinstalling previously existing) cheap, flimsy curtain rods.

I do lots of tasky stuff like hedge trimming, bark mulch, pruning, cobweb removal, stuff that I can do without being tied up all day on a place, but still saves a few grand a year. 

During our remodel, one of the units kept smelling like weed, even after new flooring, cabinets, trim, paint, etc.

Ripped up old carpets and laid new laminate flooring all throughout, new trim, a lot of drywall work due to lack of temp control, new paint all throughout, added wainscoting over tile bathroom and hallways as easy and inexpensive fix.

I GC'd an addition to my house 2 years ago (TN) and I have a lot of relationships in this business, and I still spent a little over $100/sf and that didn't include insulation, electrical, HVAC flooring or finish trim work.