best chapter facilities?

Sororities:

Kappa: nicest outside/exterior
Zeta: biggest overall (i think, but maybe theta)
Adpi: feels the most like a home (imo)
I also really love TriDelts natural lighting/living room area

Actually, now that I think about it all the houses are pretty nice. You shouldn't choose a chapter based on the house itself bc we are all really lucky to have great houses. The only reason why you'd want to choose a house based on size is if you really want to live in. In that case I think ZTA and Theta are your best bet.

Frats:
I feel like most of the frats are pretty similar. But Chi Phi is unusually homey inside. Living room looks like a middle class mom decorated it

Been awhile since I've been in the Greek system at Cal. I thought all the sororities had really nice homes. Each had a unique look and backstory.

Kappa's house is a Julia Morgan design. AOPi/Delta Sigma house was designed for them by the dean of the architecture school and has the AOPi letters incorporated into the foyer design. It also has some crazy bay views and unique rooms. Gamma Phi had a really nifty art-deco looking house. AGD had beautiful, comfortable common rooms. Not sure if anybody took over their house after they left campus. AXO had a roof that was famous for sunbathing. I think my favorite house is Sigma Kappa's. It has a beautiful tudor exterior.

Fraternity houses weren't anything special. I remember feeling like we were lucky if they were clean when we'd drop by. ;-)