You're just about there. I think I started breeding rats and mice when I hit a dozen or so. It's really nice having any size rodent to choose from at any time if you have young snakes. However, smell is a real concern. I don't like the smell of rats. I can smell them even in a freshly cleaned cage. I would avoid a basement if it's at all humid which most basements are. The humidity really brings out the smell.
It's unfortunate that snakes and rodents like the exactly opposite environments. Snakes need warm and humid and rodents need cool and dry. So it makes it somewhat of a challange to keep them in the same room.
My first word of caution would be that it's a ton of work. I spend about 99% of my time with rodents and 1% with snakes!