It also has a gorgeous efficiency apartment above a garage, and another 2bed house on it.

Is Using Zillow to find 20-30 rental properties efficient or should I ask an agent for help? 

The first quote came in at $5,200 to install a 80% efficiency furnace and an AC unit. 

I want to be efficient as possible. 

The big thing is to learn to analyze your deals, be efficient on rent and to learn to turn a profit. 

What are my options for high efficiency toilets?

I know that direct mail isn't the only way to get deals, but based off of my experience it tends to be the most efficient way.Feel free to reach out if I can answer more questions for you.Gary Harris

., new electrical wiring through-out and upgrading to 200 amp, new plumbing supply and drain through out (except maybe for the cast iron stack), new high efficiency furnace and air conditioning unit, new ducts, new insulation, new drywall, new roof(s), new siding, new windows, new floors, new doors, new fixtures, new kitchen, new bathrooms....basically everything is new plus changing the floor-plan some.I am not ready to share any more details at this time.

Would it be more efficient targeting just 1-3 specific zip codes?

While their focus is on energy efficiency, they have all kinds of analyses they run to look for energy leaks.