I have a dog bed idea that I'm going to try pretty soon. Every spring our town has "Spring Fling", when we can put furniture, etc., on the curbs for the trash men. I'm going to drive up and down the streets looking for good sofa cushions and cover them with an appropriate fabric.

The reason I'm doing it is because sofa cushions are much thicker than any dog beds I can find. But - if you did something like that and the dogs tore it up, no biggie because it was free anyway! You could pick up several and not even bother covering them!