The price for your chin could vary widely. I paid $500 for my extra dark ebony twins ($250 each), $300 for my violet wrap and $225 for my extra dark tan. These prices are a little on the "high" side but a lot of that has to do with my geographic location. At one point I was offered twin **** beige girls for free including a FN 141 and I passed because at the time I did not want any more chins. If you want a pet I'd definitely recommend looking into rescues and Craigslist as there are plenty of chins that need a good home!
Supplies...they can be a little pricey. I bought a FN 181 for my single girl for $105 including shipping because ferret.com was/is having a sale and I had a coupon. My trio lives in a Quality Cage Mansion that was very expensive to buy and have shipped...maybe around $300-$400? My husband paid for their cage so I'm not sure, I just know it was around that range.
Then, you of course have to provide feed, hay, chew sticks, dust bath and some sort of bedding. You'll need a water bottle, food dishes and a dust bath container. These things are really the bare minimum and of course can range in price depending on where they are purchased. Extras like toys, fleece accessories and beds can get pricey but they are totally optional! Most of us just really love spoiling our fur kids.
Vet bills can vary widely. I am lucky and I have not (knock on wood) had to take any of my girls to the vet yet in the two years I've owned chins. I do have money ($2,000) set aside in cash for vet emergencies, and a credit line ($4,000) set aside for extreme emergencies. I have pet insurance for my dog which I love but it seems exotic pet insurance is hard to come by!
I'd say do your research, look at products online and browse the classifieds section here for more info.
Good luck!