I have had rats for about 8 years.(obviously not all the same rat) my first was daisy, I had only her and I had alot of time to spend with her so she was the friendliest. Next was Lizzy and I had her a year prior to going to college and it was not even a choice to me, I just took her to college with me and would do what it took to make it work. She was kept in a single story cage in the closet of my dorm. The door to the closet was open all day/night. She was out of her cage whenever I was in the room. For room inspections I put her whole cage into a tuppeware container and put it on the very top closet shelf just long enough for it to be done. While in college my friends loved her so much that two got rats also and we had a great time with our secret pets. I took her home for holidays by putting her whole cage into an EGG cardboard box and carrying it right out the dorm. After she passed I got two more females. Delilah(my first dumbo rat) and Ashanti who lived roughly 2 years. after they passed my fiance wanted some boys so we got Knibbles and Gerald who we got both as babies and lived in a large ferret cage. They are WAY messier then the girls we have owned. I would not say the smell is much worse just the way they pee all over and poop anywhere. I also got two more girls who are kept in another large cage. Lily and Jasmine. For unknown reasons Gerald died before two years and Lily died about the same time. I now have one girl and one boy, still each in their big cage. I was only ever bit by one rat. it was not mine, it was a grown female in a pet shop who must have not been held much. I have always gotten mine as babies and they were always VERY LOVING and WONDERFUL fun.. Rats are great IF you read up about them and are prepared. They are certainly not great when you get one without knowing about the little things they do that you have to get used to. They make noise and shred things at night. They do dribble TINY drops of pee when they walk, they do chew and their cute little hands can grab and pull things into their cage, they they will chew it. Be prepared and you will have tons of fun.
Enjoy.
Heather