A good quality chin pellet like oxbow or mazuri or a show rabbit feed. Unlimited amounts of grass hay. No fresh veggies or fruit ever they can cause bloat in chins they are super sensitive. If you want to give a treat a piece of plain shreded wheat or a cheerio once a day is ok. Safe dried apple wood or wood chews from the pestore are also good for their teeth. www.petproductsbynature.com sells safe chinnie toys and chews.
All chins from petstores, rescues, and quality breeders I've seen for $100 minimum on the plain colors. The uncommon colors can be several $100 to even several $1000. People with occasional litter from chins they bought at a petstore might sell them for $50 and I've seen pairs offered to rehome for $100-$200 depending on color and what they come with. Overall they aren't exactly cheap meat or fur. Especially with their somewhat demanding care. My sister's room mate killed 2 chinchillas by not interacting with them enough. My sister eventually kicked her roommate out because she couldn't stand behaviors like that.
No fresh veggies or fruit ever they can cause bloat in chins they are super sensitive.
They are sensitive but that doesn't mean they can't have fresh food. Their natural diet is forage (grass) and vegetation. The reason you feed hay to an animal is because it would normally eat grass so we dry grass into hay in order for it to keep. Pretty much any animal that is fed on mostly hay can be fed on a diet of nearly only grass. The problem is in order for any animal to keep the bacteria needed to digest something they need a constant source of that particular food and they need to start with very small amounts. People either start with too large of amounts, stop and start a food, or feed such limited variety that the animals don't have the bacteria and aren't making the enzymes needed to aid digestion of that food item. In some animals it doesn't matter. In others like chins it really matters. Personally I prefer to feed my animals as natural of diet as possible without pellets. I've fed several south american rodents from the common guinea pig to the more uncommon degu without a commercial pellet on what I could find as the equivalent to their natural forages.
Also this site not only has links to what they'd eat in the wild but seems to reinforce what I've seen on UK forums that chinchillas there are not fed this strict no vegetation or fruit diet the US chin keepers have started to follow: http://www.galensgarden.co.uk/herbivores/chinchilla/diet.php
