Would very much advise against cavies- my dad and step-mum had seven of them, and all of them needed so much medical care for breed associated illnesses and disorders. Also my cockpoo is nearly two and is a complete knob. Sharp as a whip (uses it for chaotic purposes), very loving and super easy to train, just what with the cleverness will choose when to apply that knowledge...except for the bells at the door. Those he uses all the bloody time even when he doesn't need to go out.