If you're going to get any type of cage/aquarium pet.
It may sound strange but you're likely best off with a rat.
They're friendly, clean, and very smart (even trainable)

reptiles are low maintenance and for the most part have no real odor (unless you go months or something without cleaning). while cold blooded and needing heat, if your place is hot in t he summer, you could get by with just a heating pad undercage for winter months. not to mention, once you have a six foot red tail boa at the entrance of your home, makes for good party talk.