Should we get a turtle for our family?

So, my husband and I have decided we might want to purchase a Red Eared Slider (Turtle). We were down at his mother's for Labor Day weekend, and she purchased one for his little brother. I absolutely adored this turtle, but thought perhaps the setup they had there was insufficient for a turtle. They simply have an aquarium with no water or rocks or background sitting on the floor behind his little brother's bed. Sometimes he'll fill the bath tub with some cool water and let her swim around and occasionally she will get to go outside. We were thinking a more appropriate setup would be a little more costly, probably around $100 or so for the turtle to be really happy in her environment. Any experience with turtles? They need proper lighting, right? Since they are semi aquatic, they'll probably want water available but not all the time. Is anyone a turtle fanatic? Do they have a pungent odor even if they are cleaned up after? Thanks for your input in advance.