I too would want to know why this breeder is giving up this gal. But I too agree with spaying her. And besides the regular pre-surgery blood work I would have a BATS done Bile Acid Test - it can tell you more about the health of her litter.
Hair being thin could be a function of pregnancy and whelping or just be the type of coat she has.
Ido hope she fills your heart with happiness!
