What is the bread and butter houses?

Are you talking border zones, or bread and butter neighborhoods..

The bread and butter homes are the 3/2s. 

Purchase price: $615,000 A bread and butter 2/1 1600 sq ft duplex.

Sadly, the market is very limited.I think the bread and butter would be SFRs in this area.  

Lived off of Saltines and Peanut Butter.

No bread and butter items purchased only business costs to make money.  

@Kyle Murphy Milwaukee is my bread and butter!  

With the overpowering smell of "fake butter" popcorn, the explosive sounds, all of the light flashes, and being expected to just sit there for 2 hours, barely moving, made me vow "Never again."

On the flip side I buy my clothes at thrift stores, I eat cup of noodles, cereal, and peanut butter and jelly and I nearly own my car (I will have paid it off in 2.5 years because I bought something I could afford and have been making large payments on it as quick as possible.