89 Camry Brakes

I'm having problems with my brakes. Pedal is spongy and travels pretty much to the floor. Pumping brings it back up, but only for a very short time. Master Cylinder is brand new, and that didn't solve the problem. Is it my brake booster? and if so, how hard is that to replace?

bleed your brakes and check for brake fluid leakage. The air has to be getting in somehow.

Brakes have been bleed, and there are no apparent signs of fluid leakage. It's leaving me stumped.

Bleed them again. I bet it was not done well.