That so great that you're doing so much research BEFORE getting your animals.
In reference to other tidbits to share, I have learned SOOOOO much by just going through other posts. May be an ideal thing for you to do too. Many other, more experienced owners will probably chime in, but the food, the cage, the toys, the bedding, and then, the furbabies! I think you posted you were looking at getting them at a breeder? (I have bad ADHD, sorry if I got you confused with someone else). If so, that's great. Rescues are awesome too. So many people on here are so knowledgeable about various aspects of rat care. You're in the right place. About the shedding, I can tell you, yes, most do. At least mine do. Some are not as noticeable, but I have a velveteen and a rex, and to be honest, they seem to shed the most. I think that it's also a little more noticeable from my white haired rats since I tend to see their hair more often, although I'm sure my dark furred guys shed as well.
