You own a store, you sell 2 brands, which?

Thought experiment:

You run a store which sells used and new gear from any point in history.  The catch is you can have exactly 2 brands.  One of electronics one of speakers. 

Defunct brands are OK as are those current with long histories. 

What brands are they? 
Yamaha and Macintosh. Yamaha covers every aspect of AV from consumer gear to audiophile. Macintosh will satisfy the snobs. 
Schiit and Klipsch.
They both range from affordable to audiophile.  

I've owned neither...yet.
VTL and Wilson.

Hey, if nobody buys them, I still get to listen to them all day.
Same thing I sold back in the mid-1970's - 1990's:

Audio Research and Magnepan

That's about all you need for the major components if you are actually interested in accurate reproduction.