Hi everyone, I am here looking for advice. I am concerned I am not providing the 'typical' care for my 3 guys, Meeko, Teddy and Hershey, and looking for some guidance/advice. So let me give you a little background and tell you the situation. 

A year ago, my girlfriend and I got three ferrets and were very excited about it. The main reason for getting them were because she is allergic to cats and dogs. Since then, we have broken up and I am now the caregiver of the boys. I have also moved 2000+ miles away and their room is a little smaller than their previous one.  The current room size is 12x13. I typically will have their cage open for ~3 hours in the morning and ~2 hours in the evening. I do not let them into the rest of my apartment, so this is the only space they explore and play in. Lots of toys (but I haven't introduced new toys in couple months) and tubes, etc.. Occasionally, meaning ~2 times a week, I'll hear dooking and I do see the dance of joy often. Rarely do they sleep individually, and their favorite spot to sleep is in one of their hammocks, stacked on each other. They all are eating and drinking normally, and play with each other normally. So, is this a typical setup for a group of three ferrets?

Here are questions:

1. Do ferrets need to have my entire house to run through? Is their room enough space for them to be happy?
2. How often should I be buying new toys?
3. Am I doing everything okay? 

I just want to give them the best lives I can. Any help is appreciated! Thanks.