OK. I've owned rats since I was about 16 (argh! 39 years).
1 rule: It is a pet not a threat, If it bites and draws blood it gets vetted out of the world. It is a nasty character trait that can rarely be overcome. I have given up taking in scaredy rats that bite as they can't change. They cope for a while but will bite again when they get stressed, woken up, deprived of a treat etc.
BUT very few rats do bite - loads of them nibble you, have a chew on your nails, but few bite.
If you want a singleton, go for a male. But you must be able to give it 4 - 8 hours of quality time a day. They are lazier, cuddlier (eventually) and get bigger. But you DH has to be a confident man as a boy rats 'maltesers' are unfeasably large and the human male can feel quite unimportant by comparison
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Get 2 girls, they are more wriggly, more trainable and more sociable without being the living pillow male rats can become.
Don't be tempted by the rat/ferret walking harness. It may be amusing trying to get it on your rat but eventually your rat gets bored and will let you succeed. Then, when you do the walkies bit, they'll play along until you relax and then just walk backwards out of it and disappear
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Do try to get them from a breeder. DO NOT rescue any. Try to avoid Pets R Us, or similar. Having said hat my last 6 matties have been from Pets R Us and they have all been lovely. I got them all from homes that hadn't thought about it properly.
All rats come with tails, and teeth. The tails are just too much for some people. Rats teeth slope backwards, so if your rat tastes you, and they all do, you can't pull your finger away as your rat won't be able to open it mouth, you have to trust. Easy to do as a biter chomps down and lets go, a taster nibbles hangnails and cuts your nails for you - also known as Barber Rats, they will happily graze the hair off your forearms.
I'll stop now. Can you tell I love them
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