Not to correct, but from my experiences your lucky if your rat lives to 3yo. It would be exceptional to live beyond this age. I would say average 2-3years if no health problems. Mice and rats, totally different. Unlike mice, rats do not smell as much. Ofcourse any animals poop will smell if you dont clean cages. The rat themself doesnt have much smell and they are forever cleaning themselves, so aslong as you keep cage cleaned and use something like breeders choice litter there would be very little aroma.
My kids have been around rats from young age, I would say they are the best small animal pet HOWEVER any young child should be supervised for the poor animals sake. Even with my kids being used to ratties I had an incident with my son stripping one the male rats tail (BIG ouchies!!) It can happen even under watchful eyes. Kids can be evil with animals, they are just plush toys to their tiny brains.
*forget whos pic was posted, just wanted recommend to cover the wire base, or remove it and just use the plastic as base. The wire bases arent good for their feet. Plus easier to clean that yuckies stuck in wire lol