What are some good apartment pets (details)...?

My dad and I are "right-sizing" into a apartment because both of my sisters just went to college. We already have a 14 year old dachshund who is still "rolling" along. But I would like a small playful pet. We will either be living on a floor apartment (hopefully), an apartment 7 stories of the ground (probably) , or a penthouse (18th floor - if we can get a wall or two torn down). I would like a more playful animal that is sweet, and requires normal attention (I could play with it about 2 hours on weekdays, and as many hours as needed on weekends). But, unfortunately, I will be only staying with my dad about 3-4 days a week. I do know how to take care of plenty of animals (cats, dogs, hamsters, fish, etc.) but would like something "new". I do volunteer at the SPCA so I am used to cleaning messy cages :). I am 13 going on 14, and would like, I don't know, a sugar glider (which do require much attention) or a parakeet, or something in that area. Only things I can't have FOR SURE or turtles, snakes, ferrets or rabbits unless the apartment is "safe". Please answer and thanks!