Blythes are not BJDs. They aren't strung, they don't have ball joints -- heck, they don't even have articulation at all!
An official, full size Blythe usually costs over $100. If you're a newbie at customizing them, you should consider looking up Blybe on eBay -- those are knock-off Blythes for a fraction of the cost, and they're very nice quality for what they are.